Enabling navigator, does not do anything useful yet
Fix the direction of the override switch for the new state machine
RC3 usually used as Throttle, but trim was set to 1500 by default.
It should be 1000 by default.
There were unintialized variables.
(control mode was not updated)

Also, new flags (xy_valid etc) were considered.
Airframe No. 21. 22 have been added.
That is for general ESC with PX4IO (frame geometry defined)
easystar startup script: load mixer from sd-card if available
Merge pull request #427 from thomasgubler/sd_mixer

easystar startup script: load mixer from sd-card if available
Hotfix: Improved file test
Merge branch 'master' of github.com:PX4/Firmware
tone_alarm: add GPS warning tone
Better voltage scaling for Iris
Start digital airspeed sensors as default
Hotfix: Ensure that a minimum of 10 degrees pitch is set on takeoff
Update sensor_params.c

Not necessarily modify this on initial.
Merge pull request #426 from limhyon/master

PX4Flow, and several tiny things enhanced.
Merge branch 'master' of https://github.com/PX4/Firmware into geofence