Graphviz with perl binding

Sorry, this become a monster. Originally, it would be only the GraphViz2 perl module, but it had more dependency that I expected. Especially the GraphViz2 perl module have annoyingly lots of perl module dependencies during the test phase. 
please fix indentation here, otherwise good to go in, nice job @hajgato!

```python
dependencies = [
    (python, pythonversion),
    ('PCRE', '8.35'),
]
```