empty bird and mouse classes

Signed-off-by: Alexander Skjolden <alex@plastboks.net>
hooking gradle up to idea

Signed-off-by: Alexander Skjolden <alex@plastboks.net>
preparing for TexturePacker

Signed-off-by: Alexander Skjolden <alex@plastboks.net>
small fixes for movement calculation, not completed

Signed-off-by: Alexander Skjolden <alex@plastboks.net>