copies: rewrite copy detection for non-merge users
The existing copy detection API was designed with merge in mind and
was ill-suited for doing status/diff. The new pathcopies
implementation gives more accurate, easier to use results for
comparing two revisions, and is much simpler to understand.
Test notes:
- test-mv-cp-st.t results finds more renames in the reverse direction now
- test-mq-merge.t was always wrong and duplicated a copy in diff that
was already present in one of the parent revisions
Test document extraction
$ "$TESTDIR/hghave" docutils || exit 80
$ HGENCODING=UTF-8
$ export HGENCODING
$ for PO in C $TESTDIR/../i18n/*.po; do
> LOCALE=`basename $PO .po`
> echo
> echo "% extracting documentation from $LOCALE"
> echo ".. -*- coding: utf-8 -*-" > gendoc-$LOCALE.txt
> echo "" >> gendoc-$LOCALE.txt
> LC_ALL=$LOCALE python $TESTDIR/../doc/gendoc.py >> gendoc-$LOCALE.txt 2> /dev/null || exit
>
> # We call runrst without adding "--halt warning" to make it report
> # all errors instead of stopping on the first one.
> echo "checking for parse errors"
> python $TESTDIR/../doc/runrst html gendoc-$LOCALE.txt /dev/null
> done
% extracting documentation from C
checking for parse errors
% extracting documentation from da
checking for parse errors
% extracting documentation from de
checking for parse errors
% extracting documentation from el
checking for parse errors
% extracting documentation from fr
checking for parse errors
% extracting documentation from it
checking for parse errors
% extracting documentation from ja
checking for parse errors
% extracting documentation from pt_BR
checking for parse errors
% extracting documentation from ro
checking for parse errors
% extracting documentation from ru
checking for parse errors
% extracting documentation from sv
checking for parse errors
% extracting documentation from zh_CN
checking for parse errors
% extracting documentation from zh_TW
checking for parse errors