Some improvements

Added message notifications.
Added new landscape layout for tablets.
Add time stamp to chat window.
Remove trailing whitespaces from incoming messages.

New layout features

Added message notifications when app is in background.
Added landscape layout with both chat and map visible for tablets.

Ready for F-Droid

This release is for ESP32 DisasterRadio V1.0.0-rc.1.
It might fail with older versions of the DisasterRadio app