[FIX] Better multi-server support for push notifications

[FIX] Notification not showing after logging out and log in with different user on the same server

[FIX] Test notifications not showing

Add support to push messages not containing a an ejson field and thus having no more than a message an a title. This way, a simple notification should be shown and not attached to any real channel list of messages

[IMPROVEMENT] Update gradle-wrapper.properties by adding SHA-256 comparasion

[BUG] Fixed (edited) msg shown when deleting a message

[RELEASE] Merge develop into beta

[FIX] Broadcast message replies showing outside of rooms

[FIX] Do not reschedule failed sending if the API returns inconsistent

[NEW] Add support to broadcast channels

merge

[NEW] Shows favorite message list.

merge