changes
many additions
added try-catch in Animation::frame()
added reloadable resources fixes #20
corrections
cleanup
changes
first stable version of new brush system
removed nTranferable -> Message and MessageHandler should do that task
SetTilesRequest can now tranmit more than 1 tile at once. Finished SingleBrush
removed commented-out code
Merge pull request #25 from Maxomann/gui+brush

New Gui+brush are working.