Revision 1496470

Add new 'http-chunked-requests' configuration option to control using
of chunked transfer encoding for HTTP/1.1 servers.

* subversion/include/svn_config.h
  (SVN_CONFIG_OPTION_HTTP_CHUNKED_REQUESTS): New.

* subversion/libsvn_ra_serf/ra_serf.h
  (svn_ra_serf__session_t): Add USING_CHUNKED_REQUESTS flag.

* subversion/libsvn_ra_serf/serf.c
  (load_config): Parse 'http-chunked-requests' configuration option.

* subversion/libsvn_ra_serf/util.c
  (setup_serf_req): Set Content-Length if USING_CHUNKED_REQUESTS is zero.

* subversion/libsvn_subr/config_file.c
  (svn_config_ensure): Mention 'http-chunked-requests' in 'servers' file 
   template.