Minor installation issue if only cloning last commit
If I clone pystencils with `--depth 1` the function `version_number_from_git()` in `pystencils/doc/`
will crash during `python setup.py` since `git tag` will return nothing:
```
$ git clone --depth 1 --branch hyteg git@i10git.cs.fau.de:pycodegen/pystencils.git
$ git tag
$ python3 setup.py develop
Traceback (most recent call last):
File "setup.py", line 52, in <module>
version=version_number_from_git(),
File "/builds/terraneo/pystencils/doc/version_from_git.py", line 18, in version_number_from_git
latest_release = get_released_versions()[-1]
IndexError: list index out of range
```
issue