Features:
* Polling is now done with since=<id> API, which makes deduping easier (#165)
* Turned JSON stream deprecation banner into "Use WebSockets" banner (no ticket)

Bugs:
* Long-click selecting of notifications doesn't scoll to the top anymore (#235, thanks to @wunter8)
* Add attachment and click URL extras to MESSAGE_RECEIVED broadcast (#329, thanks to @wunter8)
* Accessibility: Clear/choose service URL button in base URL dropdown now has a label (#292, thanks to @mhameed for reporting)

Additional translations:
* Italian (thanks to @Genio2003)
* Dutch (thanks to @SchoNie)

Thank you to @wunter8 for proactively picking up some Android tickets, and fixing them! You rock!