Handle authentication 401/403 responses only one time.
Handle authentication 401/403 responses only one time.

* auth/auth.c
  (serf__handle_auth_response): Discard *all* response body before handling
   authentication. 


git-svn-id: 683495cb1553624b05a54e2ba9533425f69cf277@1399 61a7d7f5-40b7-0310-9c16-bb0ea8cb1845

coapp-packages/serf,coapp-packages/serf,coapp-packages/serf