Added support for RPK file format (a single file to contain all game data files) and -rpk <filename> command.
Added the ability to specify new sound effects for game events that were different but used to share common sound effects.
Added specification of new / linked sounds via an optional SOUNDLNK.HOV file.
Added the ability to set the erase color (barColor) from the game configuration file (GAME.HOV).
Fixed a bug with the incorrect initialisation of the Drone's target.
Disabled clearing of keyboard state when starting a level.
Added display of enemy statistics to intermission screen (kills / total).