libsmaccmpilot: Tune PID values for HIL a little.
stabilize_hil: Send GPS_RAW_INT to get mapping in Mavelous.
libsmaccmpilot: Add rate stabilization for yaw.

- Rename "stabilize_axis" to "stabilize_from_angle".  Used for pitch
  and roll.
- Add "stabilize_from_rate" and use for yaw.