Add documentation to asDocument

Change-Id: I6ff66a2d9c2c02714add514553f95eab1e2b4640
Fix upload progress bug:
https://github.com/koush/AndroidAsync/issues/75

Change-Id: I8da49dead9ec09e6b653d5bed42575de4add8024
WIP: GIF support

Change-Id: I91a5a5116fa642f0f9bd6376487d4e1532db4f06
Static GIF images are now supported.

Change-Id: I4b8093000f876036826004b05d794aaa281a98ce
animated gif support!

Change-Id: Iacecd4ebf05453ccc6640ba14bc579e5f2a79abd
remove comment

Change-Id: I87b14fb38a846c242e68e8d8b878719cee9193a6
fix up invalidate scheduling

Change-Id: I3c3b3d6b6c5cfc443b5e698e6188e80c6777476b