Fixes the problem that inserting, removing or fading didn't start animation on Mac.
added .gitignore
remove .DS_Store
Remove xcuserdata
podspec update
Merge pull request #511 from ddwang/master

podspec fix
Merge pull request #502 from Ashton-W/remove-junk

Remove junk
Merge pull request #472 from willyliu/master

Fixes the problem that inserting, removing or fading didn't start animation on Mac.