tests/test-simplemerge.py.out

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

....................
----------------------------------------------------------------------
Ran 20 tests in 0.000s

OK