encapsulated access/use of the functionalities provided by the DroneEvents instance field.
encapsulated drone gps instance fields.
encapsulate access to the drone Heartbeat field instance.
encapsulate access to the drone Type, Parameters, and State field instances.
encapsulated access to the VehicleProfile field instance.
completed Drone class fields encapsulation.
Updated structure of the drone interface.
parametrized 'OnDroneListener#onDroneEvent method signature.
typo: changed 'previus' to 'previous'
changed isFailsafe to isWarning
Merge pull request #990 from squilter/sebs_august_refactorings

Sebs august refactorings
Merge branch 'master' of https://github.com/DroidPlanner/droidplanner into feature_encapsulate_drone_model

Conflicts:
	Android/src/org/droidplanner/android/activities/FlightActivity.java
	Android/src/org/droidplanner/android/fragments/FlightActionsFragment.java
	Android/src/org/droidplanner/android/fragments/mode/ModeFollowFragment.java
	Android/src/org/droidplanner/android/maps/providers/google_map/GoogleMapFragment.java
	Android/src/org/droidplanner/android/maps/providers/osm/OSMapFragment.java
	Android/src/org/droidplanner/android/notifications/PebbleNotificationProvider.java
	Android/src/org/droidplanner/android/notifications/TTSNotificationProvider.java
	Android/src/org/droidplanner/android/widgets/checklist/CheckListSysLink.java
	Android/src/org/droidplanner/android/widgets/checklist/row/ListRow.java
	Core/src/org/droidplanner/core/MAVLink/MavLinkMsgHandler.java
	Core/src/org/droidplanner/core/drone/variables/State.java
	Core/src/org/droidplanner/core/gcs/follow/Follow.java
	Core/src/org/droidplanner/core/gcs/follow/FollowAlgorithm.java
	Core/src/org/droidplanner/core/gcs/follow/FollowLeash.java
updated 'Follow' notification logic to make use of the drone event
message queue
refactored following the update to the 'Follow' api.
updated event label to signal stop of 'FOLLOW' mode.
add missing dependencies required by eclipse to build with the added mapbox map implementation.
use is_flying bit from drone, don't make it up
Only send new guidedPoint in follow-me if accuracy is <10m
Put ROIPoint 1m above the phone, so that the camera doesn't aim at the pocket, but at the person's head
Fix the issue with `distance from home` not updating.