resolved minor issues with v.0.6.0a

Resolved minor issues with previous version

moved to python 3.7

Moved to Python 3.7 with dataclasses!

support for bz2 input files

Now instead of plain .osm files, they can also be provided as input when they are compressed as bz2 (see bz2 Wikipedia).

networkx support and fixed contraction logic

• added networkx support (output)
• rewrote contraction logic which fixed several bugs

Bugfix for processing UTF-8 symbols in osm files

minor bugfix release that helps in processing UTF-8 *.osm files.

Python3 only release with type information

Types (#62)

* type information added

v0.3

Update README.md