UK: submission serializer
UK: add xform submision api endpoint
UK: more permissions tests
UK: move TemplateXMLRenderer to onadata.libs.renderers
UK: submission urls to point to XFormSubmissionApi
UK: refactor _make_submission to call the submission function directly
UK: ensure we have a user profile
UK: authenticate subission with digest
UK: do not add xml submission as attachment
UK: allow head requests to XFormSubmissionApi.create
UK: update tests
UK: StaticXMLRenderer
UK: OpenRosaHeadersMixin
UK: briefcase api on api app
UK: test views
UK: return xml for for expetions
UK: refactor _extract_id_strings, add BrowseableAPIRendere for docs
UK: for head requests ensure we return a proper OpenRosa response
UK: test head request on upload
UK: update test