Finish issue #1712.  Teach cvs2svn to clean up after itself.  
Finish issue #1712.  Teach cvs2svn to clean up after itself.  

Patch by: François Beausoleil <fbos@users.sourceforge.net>
          me

* tools/cvs2svn/cvs2svn.py
  (pass5): New.
  (_passes): Add reference to pass5().
  (usage, main): Mention and handle new --skip-cleanup option.

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