don’t allow deletion of RMDirectory’s.
Merge branch 'develop' of https://github.com/spritebuilder/SpriteBuilder into develop
Merge branch 'develop' of https://github.com/spritebuilder/SpriteBuilder into develop
remove bad calls to pngquant and optipng for the benefit of apple submission.
Merge branch 'pngquant' into develop
Merge pull request #621 from jtwigg/develop

Apple submission fix.