emoji-views: Add scroll offset

We don't need to wait until we have the user JID given that this is just
a view being instantiated.

I think why do not come archives from group chats, and it turns out that you need to add "groupchat" in options. I spent half an hour searching in the documentation, and half an hour searching in the convers tests. And finally found in tests.

The problem was that the `emojisInitialized` promise was re-created upon
logout and then no longer resolved upon subsequent login.

The `_converse.api.promises.add` method now takes another parameter
`replace` which determine whether it should be replaced upon logout or
not.

The `emojisInitialized` promise will now not get replaced.

- Rename `chatRoomOpened` event to `chatRoomViewInitialized`
- Rename `chatBoxInitialized` to `chatBoxViewInitialized` and trigger only for `ChatBoxView` instances.
- New event `headlinesBoxViewInitialized`
- Trigger the `chatBoxInitialized` event when a new `_converse.ChatBox` is opened.

Bumps [npm](https://github.com/npm/cli) from 6.11.3 to 6.13.4.
- [Release notes](https://github.com/npm/cli/releases)
- [Changelog](https://github.com/npm/cli/blob/latest/CHANGELOG.md)
- [Commits](https://github.com/npm/cli/compare/v6.11.3...v6.13.4)
Signed-off-by: dependabot[bot] <support@github.com>

Also replaced some lodash methods with native ones.

- Use the bare JID as indexedDB dataStore
- Collapse localStorage and indexedDB stores into one `persistent` store.
- When testing, only clear test data

Bump to latest backbone.browserStorage which adds the `clear` method

Handle any `error` IQ result or timeout from a MUC ping as indication that we're no longer joined.

Otherwise we might run into a situation where a very old,
cached MUC that's being restored has `connection_status` set to ENTERED
(and the user happens to be in the MUC via another client)
and then restores cached messages without taking
`clear_messages_on_reconnection` into account.

we already listen for `beforeTearDown` and do what's necessary there.

`initStatus` is no longer on the `_converse` object, so the override
wasn't being applied and chat boxes get closed when the
`clearSession` event fires.

It was in any case setting the wrong key, should've been `nick`

We now distinguish more clearly between joining and re-joining a MUC.

The `enterRoom` method has been refactored away.

Instead, `join` or `rejoin` should be used, depending on the circumstances.

Don't fetch cached occupants in the `initialize` function, instead, only fetch
them if we're restoring a MUC that we're still connected to.

If we're not restoring a still-connected MUC, then we clear the
occupants cache, and the messages cache if `clear_messages_on_reconnection` is `true`.

updates #1807
updates #1808

See https://git.happy-dev.fr/startinblox/components/sib-chat/issues/96

Otherwise Converse might only realise we're no longer in the room when
the user tries to interact with it.

* Add screenshot for embedded view mode
* Add Pàdé

- Remove need for the `converse-mouse-events` plugin.
- Register `mousemove` and `mouseup` handlers only when necessary and only inside the MUC DOM element.
- Restore converse-dragresize to roughly it's original state before work started on this.
- Move `applyDragResistance` to utils.

updates #1640