Home position manager

Also:
- Remove unused code

Use import QGroundControl 1.0 to get to it

Take MissionManager off separate thread

travis-ci android add gstreamer

Change arm/disarm mavlink message usage

Support load/save

Fix APM adjustMavlinkMessage

Also understand the concept of missions which cannot be edited

This was done to support both PX4 and APM flight stack with same code

Previous code was horribly wrong.

Paramedter Editor search support

Added APM Firmware Plugin

- Also added new adjustMavlinkMessage support

Too complicated supporting both modes as editor becomes more complex

Joystick fix

travis-ci s3 deploy

Allow buttons to be scrolled

Remove HDD, HUD, HSI

travis-ci android

Add relative altitude support