Release of version 1.2

Version 1.2 of the library

• Change setup.py to use setuptools instead of distutils.core for improved functionality
• Update reference to the publication in README.md collresolve.c

Release of version 1.1

Version 1.1 of the library

- Re-implement the classifier and neural network algorithms to remove dependency on foreign code
- Fix a bug in the Python bindings where a flag was not correctly interpreted
- Add missing collresolve_radius() Fortran binding
- Re-license the library under Apache License 2.0
- Update README.md