OP-1161 Add alarm for magnetometer plausibility check
OP-1161 discard magnetometer in filters if plausibility alarm is set
OP-1161 moved mag validity check function from sensors to state estimation
OP-1161 changed the way magnetometer-errors are handled - and defaults

* ekf will ignore magnetometer errors for initialization
 (errors might be caused by not yet existing attitude estimation)
* defaults changed for filtering
* magnetometer sensor will be available for all filters, alarms need to
  be checked separately
OP-1259 PowerDelayComp addtl inverted modes
OP-1259 WIP to merge next in locally
Merge branch 'next' into theothercliff/OP-1259_Cruise_Control_Tweaks
OP-1259 First tested version
OP-975/OP-1068 replace simple scaling with a calibration matrix for magnetometer correction
OP-975/OP-1068 Fix gcs so current calibration does still works
OP-975 Remove noise calibration
OP-975 die, die my paperplane
OP-975 Add separate buttons for mag and accel calibration (UI changes)
OP-975 add an "help view" and associated graphics for leveling
OP-975 Get rid of SIX_POINT_CAL_ACCEL, implemented
separate cal for mag and accel
OP-975 Calibrating a single sensor doesn't mean reset the other...
OP-975 change BoardRotation data type to float so it can be used for level calibration
OP-975 first part of code refactoring, changed the UI to better use the available space
OP-975 fix message at end of calibration
OP-975 Split level/gyro calibrations, base level calibration on board rotation, a lot more refactoring/cleanup