Add GETTERS for Group/Unit objects to get Frequency, Callsign, Tacan info and even current Task

[TEMPEST.114]

The lack of getters in the api means that we have to create additional look up tables for all scripting spawned units/groups etc... and have to keep going back to them. 

That's memory, processing overhead, just because of a lack of useful getters on Group/Unit objects. 

Please fix this glaring omission.

[Grimes]

We have getCallsign https://wiki.hoggitworld.com/view/DCS_func_getCallsign

Granted it returns a string and not anything with the enum values.