autostart 10016_3dr_iris: yaw PID parameters updated
Port expander driver first hacky version
fw att: robustify main loop against non finite numbers and limit error output rate
fw att: pitch ctrl: robustify against non finite numbers
fw att: roll ctrl: robustify against non finite numbers
fw att: yaw ctrl: robustify against non finite numbers
ets airspeed: Support raw field
Merge branch 'master' of github.com:PX4/Firmware into master2
Fixed up SNR logging to include maximum 32 satellites (which is plenty even for future, not yet deployed global positioning systems)
perf: Allow printing to arbritrary fds
Log perf counters
Merge remote-tracking branch 'upstream/master' into fwattrobustify

Conflicts:
	src/modules/fw_att_control/fw_att_control_main.cpp
fw att: add performance counter
Merge branch 'master' of github.com:PX4/Firmware into gps_logging_dual
Introduced extended logging mode to shield general userbase from developer logging options
makefiles: check for correct arm-none-eabi-gcc version
Merge pull request #975 from PX4/fwattrobustify

Make the fw att controller more robust against infinite input
mc mixer: additional safe limiting of mixed out
navigator: takeoff fix, always reach takeoff altitude, even if first waypoint is lower
rc.mc_defaults: set default acceptance radius (NAV_ACCEPT_RAD) to 2m