Allow keyword keyword expansion in a CVS 1.11-compatible way.
Specifically, makes it possible for a clueful user to specify
slash-delimited dates rather than hyphen-delimited.
Necessary for verifying a conversion using CVS 1.11.
Patch by: Greg Ward <greg@gerg.ca>
* cvs2svn_lib/checkout_internal.py: _KeywordExpander:
- factor out date_fmt class attr
- add date_fmt_old, date_fmt_new
- add class method use_old_date_format()
git-svn-id: http://cvs2svn.tigris.org/svn/cvs2svn/trunk@4889 be7e6eca-30d4-0310-a8e5-ac0d63af7087