Add several svn_error_trace() wrappings in libsvn_ra_svn to improver error
traces while debugging in maintainer mode.

* subversion/libsvn_ra_svn/client.c
  (svn_ra_svn__auth_response,
   ra_svn_get_locations,
   ra_svn_replay,
   ra_svn_replay_range,
   ra_svn_get_deleted_rev):

* subversion/libsvn_ra_svn/cram.c
  (fail):

* subversion/libsvn_ra_svn/cyrus_auth.c
  (sasl_data_available_cb,
   svn_ra_svn__do_cyrus_auth):

* subversion/libsvn_ra_svn/marshal.c
  (svn_ra_svn__read_cmd_response):

* subversion/libsvn_ra_svn/streams.c
  (svn_ra_svn__stream_write): Add svn_error_trace().


git-svn-id: https://svn.apache.org/repos/asf/subversion/trunk@1582229 13f79535-47bb-0310-9956-ffa450edef68