Teach IO firmware that arming and lockdown are two different things, clean up arming check
Add IOCTLs to disable lockdown of an output port
Teach IO driver how to disable lockdown mode
Teach the commander to arm on the commandline
RC config params set to more useful default values - needs more testing
Remove unused field
Merge pull request #603 from PX4/rc_config_cleanup

RC config params set to more useful default values - needs more testing
IO driver: Variable name and comment cleanup, no binary / functionality changes.
Stop setting RSSI by cross-reading servo status.
IO firmware: Use right base reg value - since the wrong one had the same value this hasn’t been an issue, but it would have become one once one of them changed.
Fixed year in controls.c comment.
Add additional flags to RC topic, not used yet.
Clean up RC related metadata, put everything into the RC data page. This ensures atomic reads, makes the reads more efficient and allows for some headroom for more RC flags. The IO driver side is updated as well, however, these flags are not published yet.
RSSI and SBUS out config now handled as setup feature flags.
Allow the setup flags to control the S.BUS / RSSI port instead of doing some wild, likely incorrect, guesses.
Add support in the IO driver to control the S.Bus / RSSI port.
Differentiate between publication and signal receive timestamp, correctly set the rc_lost flag in the frame. Ready for prime-time testing.
Remove unneeded header and commented out dead code from MEAS airspeed driver
Merge branch 'master' of github.com:PX4/Firmware
Merge branch 'master' into rc_status