Fix .gitattributes to contain binary extension rules (#460)
Fix .gitattributes to contain binary extension rules (#460)

- adds *.png and *.jpg
MovingBlocks/TerasologyLauncher,skaldarnar/TerasologyLauncher,skaldarnar/TerasologyLauncher,MovingBlocks/TerasologyLauncher,skaldarnar/TerasologyLauncher