Http1.0 Compliance

This PR fix some of mismatch between rfc1945  (section 7.2 in particular) and play implementation.

Among changes:
  * Play should not reply with a body if status is 1xx, 204 or 304
  * All other status should have either Content-Length or Connection: Close
  * If no reply body is provided, Content-Length should be 0

This PR also makes the chunked reply with http1.0 remove chunking and fallback to regular streaming of the body (see #2127)