Add support for uploading files.

Change-Id: I87044263b589bf8156210c5d03c1cb3e4f4425df
add file upload test

Change-Id: Iab6b17f857a56f356de54755498c859d9c631712
Add StreamBody to Ion
remove content type
add methods which don't take length for StreamBody
Merge pull request #68 from joein3d/master

Add StreamBody to Ion
add support for bypassing the cache on requests

Change-Id: I2c78651407198aea0319ff21709d7aae2009184a
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