Merge branch 'better-chat_status' of https://github.com/linkmauve/converse.js into linkmauve-better-chat_status

updates #421

updates #421

Also, add a class `correcting` to the message being corrected, to
provide a visual cue.

updates #421

* Translated using Weblate (Norwegian Bokmål)

Currently translated at 63.3% (207 of 327 strings)

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

* Translated using Weblate (Dutch)

Currently translated at 100,0% (327 of 327 strings)

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

* Translated using Weblate (Flemish)

Currently translated at 100,0% (332 of 332 strings)

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

* Translated using Weblate (Japanese)

Currently translated at 97.8% (320 of 327 strings)

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

* Translated using Weblate (Hungarian)

Currently translated at 100,0% (327 of 327 strings)

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

fixes #421

updates #1069

Trying to use more generic CSS selectors and to extract out common patterns.

Currently we can only show the room info modal for open rooms, because
we need the Backbone.Model.

Querying the room info and displaying it for non-open rooms will be more
work and will require a separate modal.

when removing offline users who are no longer on the member lists

Highlight the currently open groupchat in the sidebar (in singleton mode).

Currently translated at 79.2% (252 of 318 strings)

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