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/

Our handler was too restrictive due to the namespace matching.
When joining a room and the room's remote server can not be found, then
the resulting error messages doesn't not have the MUC namespace.

Currently translated at 84.3% (264 of 313 strings)

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

* Allow for shift-enter to insert newlines

See issue #1081

* Update CHANGES.md

Currently translated at 83.3% (261 of 313 strings)

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

Currently translated at 83.3% (261 of 313 strings)

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

Also made a few other minor improvements and did some cleanup.

The 'dist/converse-no-dependencies-es5.js' rule is called
'dist/converse-no-dependencies-es2015.js'.
Signed-off-by: Maxime “pep” Buquet <pep@bouah.net>

Currently translated at 100.0% (313 of 313 strings)

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

Currently translated at 100.0% (313 of 313 strings)

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

Otherwise it attemtps to send out stanzas (causing `this.socket is null`
errors when using websocket).