MC: default MC_YAWRATE_I changed for all setups, navigator: increase yaw acceptance to 0.2rad ~ 11deg
Changed low threshold in px4io firmware to 10% to ensure compatibility with user configured single channel, mode switches
rc_channels topic cleanup
commander: Enforce (in presence of power sensing) that a) system is not purely servo rail powered and b) power rail voltage is higher than 4.5V on the main avionics rail
systemlib: Add circuit breakers
commander: put circuit breaker into effect
system status topic: Add support for circuit breaker
mc_att_control: Support circuit breakers
px4io driver: Add support for circuit breakers
position_estimator_inav: don't change local z on first time ref initialization
U-blox driver rework, step 1

Handle u-blox 7+8 GNSS, too.
Disabled NAV-SVINFO for now (will be rewritten as an optional feature in
a later step).
Reduced parser buffer size from 300 to 80.
Beautifications for tab size 8

Beautifications for tab size 8
U-blox driver rework, step 2

Moved satellite info from vehicle_gps_position_s into a new uORB topic
satellite_info.
Renamed satellites_visible to satellites_used to reflect true content.
sdlog2 will log info for GPS satellites only for now.
U-blox driver rework, step 3

More sat info isolation
Flush input after changing baudrate to allow driver restart w/o GNSS
module restart
Merged ubx driver part of pull request #1031
Initialize rate values

Initialize rate values (else invalid rates wil be displayed during the
first measurement interval).
Gps driver: make enable_sat_info a command line option
U-blox driver rework,, step 4

Config phase and parser rewrite
Merge branch 'master' into mpc_in_flight_lock
Remove unreferenced SVINFO length defines