fix some rename/copy bugs - delete copy information when we update dirstate hg was keeping the copy state and marking things as copied on multiple commits - files that are renamed should have no parents if you do a rename/copy to an existing file, it should not be marked as descending from its previous revisions. - remove spurious print from filelog.renamed - add some more copy tests

# repo.py - repository base classes for mercurial
#
# Copyright 2005 Matt Mackall <mpm@selenic.com>
#
# This software may be used and distributed according to the terms
# of the GNU General Public License, incorporated herein by reference.

class RepoError(Exception): pass