Release 0.1.15 (#21)

* changelog

* bump version

* run on undeprecated pythons

* use latest dev dependencies

* yield_fixture no longer required

* no longer need 'U' flag when opening files

* update mock imports

* note about python versions in changelog

Transfer to @gianchub and bump version.

fix pkg-info for pypi release

Merge pull request #6 from Overseas-Student-Living/relax_package_vers…

…ions

Relax package versions and make test DB URI more dynamic

Merge pull request #5 from Overseas-Student-Living/add-licence

add license