add rspec gem.
delete call to plotter.
replace rspec with minitest.
add first minitest spec.
Merge branch 'feature/add-testing-framework' into develop
add failing test.
fake the tests.
add contracts.
convert ints to floats.
add working euclidean distance.
Merge branch 'feature/implement-euclidean-distance' into develop
make euclidean distance less like golf.
move distance measures to own file.
bump
Merge branch 'release/0.0.2'