Implement AsyncHttpServerResponse.sendStream
AsyncHttpServerResponse: Handle HEAD requests.
Add support for content type setting in MultiPart
Add functions for getting the logging.

Change-Id: Ia12708f66e5ea7efb7ed889d0e924653f8d2fa44
Merge remote-tracking branch 'koush/master' into cm-11.0
Fix some NPE in AsyncHttpServerResponseImple.
Fix bug in ContentLengthFilter and Util.pump.

Allow the underlying AsyncSocket to cache pending data for pause/resume.
Merge branch 'master' of github.com:koush/AndroidAsync