Use absolute paths in addremove.
This is more consistent with other places in the code, which only use
the "relpath" returned by cmdutil.walk for display purposes.
#!/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