Merge pull request #190 from arup-group/fs-optional-override

retain facility locations

Merge pull request #191 from arup-group/bug-fix-odfactory

fix ODFactrory bug

Merge pull request #189 from arup-group/choice-models

Choice models

Merge pull request #187 from arup-group/module-initialisation

add submodule initialisation

add spectral clustering tests

Loosen dependency version constraints

Merge pull request #133 from arup-group/fix-scoring

Fix scoring