views: is_xmlrpc_request: fall through to decoding if request has no content-type
views: is_xmlrpc_request: fall through to decoding if request has no content-type

If the request comes without a content-type (unlikely) still attempt to
decode the body to determin if it's XML-RPC or not.

davidfischer/rpc4django,davidfischer/rpc4django,davidfischer/rpc4django