Resolves failing cirq pre-release (quantumlib#794)

Apparently prior releases of openfermion were attempting to
use scipy.linalg.expm to exponentiate sparse matrices.  Until recently
the scipy API seem to resolve the issue of using scipy.linalg.expm
instead of scipy.sparse.linalg.expm.

This issue was not surfaced until the 1.0.0dev release so some
combination of numpy/scipy pinning or depinning has revealed this
bug in openfermion.  This commit fixes the issue by converting
scipy.linalg.expm to scipy.sparse.linalg.expm where appropriate.

Update _version.py

Update _version.py

Change version for pypi release

Release v1.3.0 (quantumlib#758)

Version bump (quantumlib#749)

Version bump post cirq fix (quantumlib#739)

Add FQE API doc to devsite (quantumlib#730)

* Add FQE API Reference.

* Update path.

* Fix path to TOC.

1.0 1.0 1.0 1.0 (quantumlib#696)

* 1.0 1.0 1.0 1.0

Version cut of the stable release.

* version should be 1.0.0

Expose number preserving conversion function (quantumlib#577)

* import sparse preserving function

* format

Bump version to 0.10.0 (quantumlib#528)

* bump version to 0.10.0

* fix test