Change follow to work above home altitude only

This adds support for the new ArduSub 3.0 feature of automatically detecting
the thrusters directions and reverting the corresponding motor output if
necessary

This also removes the "dev" sufix as this was breaking a regex
for version detection.

Don't show errors from MAV_CMD_SET_MESSAGE_INTERVAL

Update for 4.0 releases

Fix correct usage of heading value

Stream HOME_POSITION on ArduPilot

Finish up follow me support

Plugin'ized follow me support

Use firmware version type, not vehicle type

Fix parameter write broken by non-ArduPilot component changes

Handle ArduPilot strangeness with respect to components and mavlink spec for parameter messages

Update ArduPilot version to latest releases only

Smart RTL support

Copter 3.7 CH#_OPT -> RC#_OPTION name change

ArduPilot for configurable mavlink stream rates

Support STATUSTEXT_LONG

Remove the concept of reserved buttons for manual control

Assume non autopilot components follow current mavlink param_value spec

ArduPilot option to not start mavlink streams

Don't starts streams from QGC side. Assume firmware side does the right thing.

FirmwarePlugin: Issue a warning upon connecting if the firmware in use is not using a stable release

Move ArduPilot preflight check handling to generic QGC

Includes support for battery 2 setup