dirstate.status: if a file is marked as copied, consider it modified
After a "hg copy --force --after somefile cleanfile", cleanfile
shouldn't be considered clean anymore.
#!/bin/sh
hg init dir
cd dir
echo bleh > bar
hg add bar
hg ci -m 'add bar'
hg cp bar foo
echo >> bar
hg ci -m 'cp bar foo; change bar'
hg debugrename foo
hg debugindex .hg/store/data/bar.i