Global revision of message severity values.
Required also change to the low priority function gcs_send_text_fmt()
on GCS_Mavlink.cpp to disable the automatic setting of priority on
messages sent by this function
The PSTR is already define as a NOP for all supported platforms. It's
only needed for AVR so here we remove all the uses throughout the
codebase.
This was automated with a simple python script so it also converts
places which spans to multiple lines, removing the matching parentheses.
AVR-specific places were not changed.
Rover now honours the Param1 setting of a time in seconds for a
NAV_WAYPOINT and the Rover will loiter at that waypoint for that
period of time.
Note that as soon as the Rover reaches that waypoint the loiter timer
will start. If you enter a different mode during this time (HOLD for
instance) the timer resets. If you then switch back to AUTO
mode and the Rover returns to that waypoint it will wait for the
loiter time configured in param1.