So that the BOSH connection will be restored before we trigger `connectionInitialized`

It's unlikely that `keepalive` needs to be set to `false`, but there are
some edge cases where it might be useful.

Here's a breakdown of the different configurations of `keepalive` and `auto_join`:

---

* auto_login: false, keepalive: true

This is the default config. Users need to log in manually, but then
Converse will try to reconnect them when the page reloads.

* auto_login: true, keepalive: true

Also very popular configuration. Used with `credentials_url` or `prebind_url`.

* auto_login = `true`, keepalive = `false`

Not sure what this could be useful for. No currently known application.

* auto_login = `false`, keepalive = `false`

Useful when you want some kind of specific action to trigger login, but
you don't want to maintain that state across page reloads.

Also relevant when using a websocket connection with anonymous login.
With websocket it's impossible to maintain anonymous sessions across page
reload because the the session gets removed server-side as soon as the
websocket connection drops and the server won't accept a full JID with
password for an anonymous connection anyway (which could happen upon
page reload when Converse tries to login in again if `keepalive` was `true`).

triggering connectionInitialized.

That way, when listening for `connectionInitialized`, we'll know when it
fires whether we've attached to a BOSH connection or not.

* Translated using Weblate (Norwegian Bokmål)

Currently translated at 70.9% (268 of 378 strings)

Translation: Converse.js/Translations
Translate-URL: https://hosted.weblate.org/projects/conversejs/translations/nb_NO/

* Translated using Weblate (Hebrew)

Currently translated at 100.0% (378 of 378 strings)

Translation: Converse.js/Translations
Translate-URL: https://hosted.weblate.org/projects/conversejs/translations/he/

* Translated using Weblate (German)

Currently translated at 100.0% (378 of 378 strings)

Translation: Converse.js/Translations
Translate-URL: https://hosted.weblate.org/projects/conversejs/translations/de/

* Translated using Weblate (French)

Currently translated at 100.0% (378 of 378 strings)

Translation: Converse.js/Translations
Translate-URL: https://hosted.weblate.org/projects/conversejs/translations/fr/

* Translated using Weblate (Spanish)

Currently translated at 100.0% (378 of 378 strings)

Translation: Converse.js/Translations
Translate-URL: https://hosted.weblate.org/projects/conversejs/translations/es/

* Translated using Weblate (Japanese)

Currently translated at 98.1% (371 of 378 strings)

Translation: Converse.js/Translations
Translate-URL: https://hosted.weblate.org/projects/conversejs/translations/ja/

* Translated using Weblate (Galician)

Currently translated at 100.0% (378 of 378 strings)

Translation: Converse.js/Translations
Translate-URL: https://hosted.weblate.org/projects/conversejs/translations/gl/

* Translated using Weblate (Lithuanian)

Currently translated at 80.4% (304 of 378 strings)

Translation: Converse.js/Translations
Translate-URL: https://hosted.weblate.org/projects/conversejs/translations/lt/

* Added translation using Weblate (Portuguese)

* Translated using Weblate (Arabic)

Currently translated at 81.7% (309 of 378 strings)

Translation: Converse.js/Translations
Translate-URL: https://hosted.weblate.org/projects/conversejs/translations/ar/

* Translated using Weblate (Czech)

Currently translated at 100.0% (378 of 378 strings)

Translation: Converse.js/Translations
Translate-URL: https://hosted.weblate.org/projects/conversejs/translations/cs/

* Translated using Weblate (Chinese (Simplified))

Currently translated at 38.4% (145 of 378 strings)

Translation: Converse.js/Translations
Translate-URL: https://hosted.weblate.org/projects/conversejs/translations/zh_Hans/

* Translated using Weblate (Turkish)

Currently translated at 4.8% (18 of 378 strings)

Translation: Converse.js/Translations
Translate-URL: https://hosted.weblate.org/projects/conversejs/translations/tr/

* Translated using Weblate (Portuguese)

Currently translated at 83.1% (314 of 378 strings)

Translation: Converse.js/Translations
Translate-URL: https://hosted.weblate.org/projects/conversejs/translations/pt/

* Translated using Weblate (Portuguese)

Currently translated at 82.5% (312 of 378 strings)

Translation: Converse.js/Translations
Translate-URL: https://hosted.weblate.org/projects/conversejs/translations/pt/

* Translated using Weblate (Romanian)

Currently translated at 34.4% (130 of 378 strings)

Translation: Converse.js/Translations
Translate-URL: https://hosted.weblate.org/projects/conversejs/translations/ro/

* Translated using Weblate (Romanian)

Currently translated at 38.4% (145 of 378 strings)

Translation: Converse.js/Translations
Translate-URL: https://hosted.weblate.org/projects/conversejs/translations/ro/

* Translated using Weblate (Romanian)

Currently translated at 54.0% (204 of 378 strings)

Translation: Converse.js/Translations
Translate-URL: https://hosted.weblate.org/projects/conversejs/translations/ro/

* Translated using Weblate (Arabic)

Currently translated at 86.5% (327 of 378 strings)

Translation: Converse.js/Translations
Translate-URL: https://hosted.weblate.org/projects/conversejs/translations/ar/

* Translated using Weblate (Romanian)

Currently translated at 54.8% (207 of 378 strings)

Translation: Converse.js/Translations
Translate-URL: https://hosted.weblate.org/projects/conversejs/translations/ro/

* Translated using Weblate (Portuguese (Brazil))

Currently translated at 63.2% (239 of 378 strings)

Translation: Converse.js/Translations
Translate-URL: https://hosted.weblate.org/projects/conversejs/translations/pt_BR/

* Translated using Weblate (Portuguese)

Currently translated at 82.8% (313 of 378 strings)

Translation: Converse.js/Translations
Translate-URL: https://hosted.weblate.org/projects/conversejs/translations/pt/

* Translated using Weblate (Basque)

Currently translated at 94.2% (356 of 378 strings)

Translation: Converse.js/Translations
Translate-URL: https://hosted.weblate.org/projects/conversejs/translations/eu/

* Translated using Weblate (Galician)

Currently translated at 100.0% (378 of 378 strings)

Translation: Converse.js/Translations
Translate-URL: https://hosted.weblate.org/projects/conversejs/translations/gl/

* Translated using Weblate (Turkish)

Currently translated at 16.9% (64 of 378 strings)

Translation: Converse.js/Translations
Translate-URL: https://hosted.weblate.org/projects/conversejs/translations/tr/

* Translated using Weblate (Chinese (Simplified))

Currently translated at 40.5% (153 of 378 strings)

Translation: Converse.js/Translations
Translate-URL: https://hosted.weblate.org/projects/conversejs/translations/zh_Hans/

* Translated using Weblate (Polish)

Currently translated at 80.7% (305 of 378 strings)

Translation: Converse.js/Translations
Translate-URL: https://hosted.weblate.org/projects/conversejs/translations/pl/

* Translated using Weblate (Chinese (Simplified))

Currently translated at 40.2% (152 of 378 strings)

Translation: Converse.js/Translations
Translate-URL: https://hosted.weblate.org/projects/conversejs/translations/zh_Hans/

* Translated using Weblate (Portuguese (Brazil))

Currently translated at 77.5% (293 of 378 strings)

Translation: Converse.js/Translations
Translate-URL: https://hosted.weblate.org/projects/conversejs/translations/pt_BR/

* Translated using Weblate (Portuguese)

Currently translated at 88.9% (336 of 378 strings)

Translation: Converse.js/Translations
Translate-URL: https://hosted.weblate.org/projects/conversejs/translations/pt/

* Translated using Weblate (Russian)

Currently translated at 96.8% (366 of 378 strings)

Translation: Converse.js/Translations
Translate-URL: https://hosted.weblate.org/projects/conversejs/translations/ru/

* Fix: async SetUserJID

If `auto_login` is false, we shouldn't log in, so we only try to log in when
it is true. Otherwise we still try to restore the BOSH session (if applicable).

rename `autoJoin` to `connect`

- Split between `login` auth and the rest (`external`, `anonymous`, `prebind`)
- It doesn't make sense to pass along credentials when not using `login` auth so avoid that flow.
- It's not necessary to pass the `reconnecting` flag to `attemptNonPreboundSession`

given that it's implicit and can cause confusion

* Don't set JID resource when logging in anonymously. The resource will be set by the server.
* Don't wipe the `id` from the session when clearing it.

So that we can remove the textarea if we're a visitor in a moderated room.

Instead optimize in other ways.

Also:
- Don't fade in when `animate` is false.
- `trimChats` now gets called in `afterShown`.
- Add now event `beforeShowingChatView`

and bump default timeout

Also let `_converse.api.waitUntil` use it if a function is passed in.

These two commit should ideally be one, but I inadvertently pushed to
remote too early.

Includes some refactoring:

- Don't send an `active` chat state notification when entering a MUC
  I can't think of a good reason why this might be necessary or desired.
- Move `setChatState` form the view to the model
- Remove unused method `handleChatStateNotification`
- Don't store `role` and `affiliation` for the current user on the
  ChatRoom object, but instead on the ChatRoomOccupant object representing
  the user.

Also update to newer strophe.js version which contains a bugfix.

Otherwise when `removeNonMembers` gets called as we reconnect, we get a
long list of erroneous leave notifications.