Exported disarmed PWM values as IOCTLs
px4io: split io_handle_battery() out from io_handle_status()

ready to add vservo and rssi
uORB: added new servorail_status object

used for VSERVO and RSSI on FMUv2
px4io: added monitoring of vservo and vrssi

publish via servorail_status ORB topic
added error_count field to sensor report structures
perf: added perf_event_count() method

this allows drivers to get an event_count from a perf counter
Merge branch 'master' of github.com:PX4/Firmware into status_monitoring
drivers: report error_count in drivers where possible
Merge branch 'master' of github.com:PX4/Firmware into status_monitoring
multirotor_pos_control: yaw setpoint bug fixed
Merge branch 'master' into mpc_yaw_fix
Merge branch 'master' into mpc_yaw_fix
Merge pull request #409 from PX4/mpc_yaw_fix

multirotor_pos_control: yaw setpoint bug fixed
Cover last potential corner case with mixers, should be totally safe now
An even number of bytes is when modulo 2 is zero, not modulo 1 is one.
Merge branch 'master' into mixer_fix
Merge branch 'master' of github.com:PX4/Firmware
Hotfix: Silence GPS driver if no GPS is connected
Merge branch 'master' into mixer_fix
Hot hotfix: Change the number of preallocated smeaphores on both boards to the same value.