fixed droneshare uploader service issues:
- fixed issues with uploader service notification handling.
- improved network connectivity receiver/detector based on http://developer.android.com/training/monitoring-device-state/manifest-receivers.html#ToggleReceivers
(TextView) failsafeView can now be written to.
Prearm failures are reported in red
Implemented watchdog to remove failsafe warnings after 2 seconds
Read arming failures out loud.
Read PreArm failures also
updated google play store link in readme
Merge pull request #922 from squilter/arm_fail_messages

Arm fail messages
Merge pull request #923 from squilter/fix-readme

updated google play store link in readme
fixes issue #911
added backward compatibility check.
Merge pull request #924 from ne0fhyk/fix_issue_911

Fixes issue #911
fixed localization issues.
Merge branch 'master' of https://github.com/DroidPlanner/droidplanner into fix_uploader_service_connectivity_detection
Merge pull request #920 from ne0fhyk/fix_uploader_service_connectivity_detection

Fixes issues with Droneshare Uploader service
Merge branch 'master' of https://github.com/DroidPlanner/droidplanner into feature_android_wear

Conflicts:
	Android/AndroidManifest.xml
	Android/src/org/droidplanner/android/DroidPlannerApp.java
	Android/src/org/droidplanner/android/receivers/NetworkStateReceiver.java