remote.Remote.urls fails

[sstancu]

It seems the fix for #694 only works if the current workin directory of the running program is within the git repository.

If the current working dir is outside the git repo, then the following (starting at git/remote.py:557)

                        result = Git().execute(
                            ['git', 'config', '--get', 'remote.%s.url' % self.name]
                        )

fails with:

git.exc.GitCommandError: Cmd('git') failed due to: exit code(1)
  cmdline: git config --get remote.origin.url