Adding workspace
Changing deployment target to iOS 5
Minor reformatting
Squashed commit of the following:

commit 3d353f5fc58116f4a05b8208b4b1ae0006ee7cdb
Merge: d00bba5 46272a8
Author: Mattt Thompson <m@mattt.me>
Date:   Tue Apr 1 07:09:55 2014 -0700

    Merge branch 'master' of github.com:chenfeng163/AnimatedGIFImageSerialization into chenfeng163-master

commit 46272a826415257e1166648391356790ede5044f
Author: 陈锋 <chenfengole@gmail.com>
Date:   Wed Mar 26 13:54:15 2014 +0800

    support image@2x.gif

commit 755fc985caab58a209e744f0b482bb856ddd4e05
Author: Mattt Thompson <m@mattt.me>
Date:   Tue Mar 25 15:16:50 2014 -0700

    Update README.md
Adding podspec
Update README