Fifth and sixth day: main game loop finished

Major:
+ Main game loop including game end
+ view_match() view now can show any turn in game
+ Map.image_in_match() renders map with tokens on it (transparency broken)

Minor:
+ Added can_capture_flag field to token types
+ Added fields for controlling retreats after draws
+ Unique to reserve and headquarters field of Country model
+ Changed flag_controlled_by field to defeated (boolean) on MatchPlayer model
+ Reworked settings.py (but ATOMIC_REQUESTS doesn't seem to work)
+ Added line count script
+ Some refactoring
+ Added TODOs