Add --quiet support to the C test framework.
Add --quiet support to the C test framework.

* subversion/tests/svn_test_main.c
  (quiet_mode, quiet_opt): New.
  (cl_options): Add support for --quiet.
  (do_test_num): When in quiet mode, don't print unexpected results.
  (main): Parse the --quiet option, failing if it is provided
    alongside --verbose.

jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion