Pip version is not up to date with source code

[ezequielp]

It seems at least this commit https://github.com/sprin/markdown-inline-graphviz/commit/b5c4c042a6e4fcb32001705cdea6445c54c1762f is not on the version you can install through pip.

This means the package fails on python 3.x

[cesaremorel]

It seems at least this commit b5c4c04 is not on the version you can install through pip.

This means the package fails on python 3.x

I've put a python and pip 3.x compatible version here.