- this ensures that the MAV_TYPE parameter is always updated
- previously it could happen that the simulator module was using a wrong
MAV_TYPE value because it only read the parameter value at initialisation

Signed-off-by: Roman <bapstroman@gmail.com>

This also removes the HIGHRES_IMU mavlink stream to the GCS. I don't see
why it's needed and it adds noticeable CPU load.

Signed-off-by: Roman <bapstroman@gmail.com>

Signed-off-by: Roman <bapstroman@gmail.com>

Ensure all data is set.

Simulator: virtual battery drain stops by default at 50% to avoid failing preflight checks to take off again
also added comments and removed throttle compensation because there is no real battery emulation with load drop

it's a lot more readable and battery draining stops exactly at the empty battery voltage which makes debuging easier because it's directly predicatable

 - GPS and battery were publishing at > 800Hz

The GPS simulation now mimicks the real driver more closely and should provide even GPS delays. The delays themselves are set by the simulator, and default to 120 ms for Gazebo

The simulation engine had the ability to pause already and properly handled load spikes, however, it was not hardened against constant drift. This addition enables it to run at a constant slower-than-realtime rate successfully.

Simulator: Compensate scale error, not just message drops. This makes the whole simulation a lot more stable

   system_source - This battery status is for the brick that is
                   supplying VDD_5V_IN
   priority      - Zero based, This battery status is for the brick
                   that is connected to the Power controller's
                   N-1 priority input. V1..VN. 0 would normally be
                   Brick1, 1 for Brick2 etc

  Battery now assigns connected from the api in the
  updateBatteryStatus, as well as system_source and priority