updates #497

Fix and improve accordingly. updates #497

updates #497

Add 3rd party dependencies

updates #497

Various fixes to code checking for server and contact client support

Hopefully later we can use NPM for them, first want to get things to work

Initial work on adding OMEMO support

updates #1094

Otherwise subtle, hard-to-reproduce bugs happen while testing.

Also, don't unnecessarily call `delegateEvents`, it also causes
heisen-breakage.

So that we can cache roster data for longer and presence data for
shorter.

after sending

Also remove the `message_storage` setting.

Instead of padding the container, pad individual elements that need it.
This enables us to have highlighting (e.g. on hover) that spans the full
width of the controlbox.

updates #1069

in the overlayed view_mode

* Translated using Weblate (Dutch)

Currently translated at 100.0% (313 of 313 strings)

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

* Translated using Weblate (Flemish)

Currently translated at 100.0% (313 of 313 strings)

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

* Translated using Weblate (Japanese)

Currently translated at 100.0% (313 of 313 strings)

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

* Translated using Weblate (Hungarian)

Currently translated at 100.0% (313 of 313 strings)

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

* Translated using Weblate (Norwegian Bokmål)

Currently translated at 84.9% (266 of 313 strings)

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

* Translated using Weblate (French)

Currently translated at 99.0% (310 of 313 strings)

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

* Translated using Weblate (Arabic)

Currently translated at 79.2% (248 of 313 strings)

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

* Translated using Weblate (Arabic)

Currently translated at 86.5% (271 of 313 strings)

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

* Translated using Weblate (Indonesian)

Currently translated at 27.4% (86 of 313 strings)

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

instead of informing all users every time someone enters the room.

so rename model and only use it in the VCards collection.