stravalib==0.9 not compatible with pip>=10

[daquinoaldo]

stravalib==0.9 contains in the setup file this import:
from pip.req import parse_requirements
But starting from pip >= 10 the module is called pip._internal.req instead of pip.req.

A (not recommended) workaround is to downgrade pip to v9 with python -m pip install pip==9.0.3.

The solution is to install (or update to the latest version) pip-tools.

More information on this Stack Overflow thread.

[daquinoaldo]

The bug is resolved with the proposed pull request #6.