Don't process --game_data if its value is empty

Closes #418
Merge pull request #437 from dorkster/bugfixes

Don't process --game_data if its value is empty
Ignore speed effects when adding hero power cooldowns
Merge pull request #439 from dorkster/bugfixes

Ignore speed effects when adding hero power cooldowns
Merge branch 'master' of https://github.com/clintbellanger/flare-engine
Fixed some more maps