tests/readlink.py

tests: add filtercr.py helper for progress tests

The two tests that used filtercr.py already used a slightly different
version, which explains why test-convert-svn-move.t changed after
switching to using $TESTDIR/filtercr.py.

#!/usr/bin/env python

import errno, os, sys

for f in sys.argv[1:]:
    try:
        print f, '->', os.readlink(f)
    except OSError, err:
        if err.errno != errno.EINVAL:
            raise
        print f, 'not a symlink'

sys.exit(0)