Corrected spelling of ResourceRetrIEver
Added Retriever injection
Automatically Injecting when adding system to game
Added explanation in comments of travis configuration file as to why all_branches: true needs to be used.
Merge branch 'master' of https://github.com/Cardshifter/Cardshifter into develop
Merge branch 'develop' of github.com:Cardshifter/Cardshifter into develop
Merge branch 'javafx' into develop