Alpha version based on scipy

Simulated annealing is now done with scipy's dual_annealing, as described in issue #5. Package is now installable through pip. This release corresponds to version 2.0.0 on pypi.

Alpha version based on mlrose

First official release depending on mlrose package. Code has been validated and is efficient, but mlrose package is not well-maintained with ongoing installation issues. Hence this is a prerelease where the next release will not be dependent on mlrose anymore.