FIX #2 - chdir(TMP_DIR); => so nuch directory

The TMP_DIR is created by the `git clone` command. `chdir` is needed
primarily for `git submodule update --init --recursive` which needs to be
executed in the local git repository directory and for branch switching, so
that we don't need to set `--git-dir` and `--git-work-tree`.
Merge branch 'hotfix/1.0.3'