release, tried to make this script much more robust.  Use
r-strings for regexps.  Junk unnecessary code that a Unixhead
probably thought was needed for Windows (replacing forward
slashes in filepaths -- Windows accepts those too).  Made
the search criteria for NEWS.txt much looser (this is the
one we seem to blow most often).  Changed replace() in
several ways:  only replace the first occurrence of the
pattern (we never need more than that, and looser searches
are dangerous when replacing all occurrences); provide
feedback on everything done; if the pattern isn't found
at all, print a noisy msg saying so.  Completed the list
of modified files in the module docstring.