Merge pull request #14 from khawkins/mobilesdk

2.2 Release: Merging mobilesdk.unstable into mobilesdk
Pass the original API error(s) along in the event of a REST request failure
Merge pull request #15 from khawkins/original_rest_errors

Pass the original API error(s) along in the event of a REST request failure
Merge pull request #16 from khawkins/mobilesdk.unstable

Network SDK: Merging master to unstable