* subversion/tests/cmdline/svntest/main.py   (usage): New function which prints usage information for a test    program.
* subversion/tests/cmdline/svntest/main.py
  (usage): New function which prints usage information for a test
   program.

  (run_tests): Remove incomplete usage information from header doc.
   Add support for --help/-h, invoking usage() and exiting if
   specified.


git-svn-id: f8a4e5e023278da1e04e203c7fe051e3c4285d88@862401 13f79535-47bb-0310-9956-ffa450edef68

wbond/subversion,YueLinHo/Subversion,YueLinHo/Subversion,wbond/subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,wbond/subversion,wbond/subversion,wbond/subversion,YueLinHo/Subversion,wbond/subversion,YueLinHo/Subversion,wbond/subversion