Fix object flag overlaps.

This pull rearranges the object flag values a little to remove the overlapping/unused ones.

OF_SAFETY is now 0x00000100, as OF_INVISIBLE was moved years ago.

The highest bit has been removed from the drawing flags and is now used for OF_HANGING (0x01000000) to remove overlap with the player name color flags. Room for 4 more drawing flags.

OF_FALSEPLAYER was not used for anything in the client and has been removed.

Minimap color flags are now set up as an enum with room for 3 more settings.

0x00002000 has been left open (was supposed to be for OF_TEMPSAFE).