Openfermion

* Updates molecular data structure to allow for use with abstract molecules.
* Fixes error in docker file and improves docker instructions.
* Some bug fixes for model Hamiltonians.
* Adds routine for mean-field state preparation circuits.

* Adds the AO overlap integrals.
* Ensures compatibility with latest version of OpenFermion.

* Adapted code to breaking changes in OpenFermion 0.1a3.
* Removed buggy example in generate_data.py.
* Updated installation instructions.

* Fixed inconsistencies in the readme and manifest.
* Removed unnecessary dependencies in requirements.
* Added instructions for installing Psi4 via Anaconda.

First alpha release of OpenFermion-Psi4. Release is mostly a fork of FermiLib-Plugin-Psi4 with adaptations to support OpenFermion instead of FermiLib.

Initial commit made on behalf of Ryan Babbush (Google), Jarrod McClean (Google), Ian Kivlichan (Harvard), Damian Steiger (ETH Zurich), Thomas Haner (ETH Zurich) and Dave Bacon (Google).

- Fixed an issue with the `scipy` dependency, which caused an incompatibility with `openfermion`