Ignoring .DS_Store files.

Signed-off-by: Esteban Torres <esteban@logn.co>
UICollectionViewLayout - TechTalk sample App. (05/24/13)

Signed-off-by: Esteban Torres <esteban@logn.co>
Merge branch 'master' of me.github.com:lognllc/sample-apps