Survey (Grid).copter. Change waypoint delay.
	Delay increments are now .1 seconds.

FlightPlanner:
	Recenter map when loading poly from file.
	Change type of "p1" to accommodate for the delay change.
Survey (Grid) HeadingHold upgrade.

The heading hold value will now adjust with the angle of the flight path.
Survey(Grid) Save "checked" for internals and footprints.

User requested survey save the checked option.
mavlink: update library
currentstate: add battery2 values
Merge pull request #605 from tristannovak/master

Survey (Grid) Delay and HeadingHold Upgrades
FlightPlanner: add distance check to dashed home line