tests/test-paths

Fix how setup.py identifies the Mercurial version.

There is a problem with setup.py where it will not identify the Mercurial
version properly when not being ran in within a repository even if
mercurial/__version__.py exists.

To fix, use mercurial.__version__.version when available before defaulting
to "unknown".  (Using mercurial.util.version() is not an option due to a
dependency issue where osutil can be referenced before it is built.)

#!/bin/sh
hg init a
hg clone a b
cd a
echo '[paths]' >> .hg/hgrc
echo 'dupe = ../b' >> .hg/hgrc
hg in dupe | fgrep '../'
cd ..
hg -R a in dupe | fgrep '../'
true