refactoring of the mavlink connection class structure.
Several core utilities not dependant on android were moved to 'Core'.
The restructuring should also fix a persistently annoying 'save to log' bug, which i think might have been the result of a race condition.
bug fixes.
bug fixes.
Merge branch 'master' of https://github.com/DroidPlanner/droidplanner into fix_savetolog_bug

Conflicts:
	Android/src/org/droidplanner/android/maps/providers/google_map/GoogleMapFragment.java
bug fixes.
added crash alert. beep beep
extracted constants
Implemented settings for warnings tts items
fixes bug from PR #1008
400 ft exceeded warning
implemented tts arming failures and renamed failsafe to warning
implemented tts setting for lost signal
extracted 121.19 to constant, moved settings to droidplannerprefs
use context.getstring(), implemented weak signal warning
implemented low batery warning
revisions based off of input from @ne0fhyk
Merge branch 'master' of https://github.com/DroidPlanner/droidplanner into fix_savetolog_bug
Merge branch 'master' of https://github.com/DroidPlanner/droidplanner into fix_savetolog_bug

Conflicts:
	Android/src/org/droidplanner/android/fragments/DroneMap.java
removed <15% battery and replaced with autopilot-reported low battery
hiding solar and wind activity checkboxes