Refactor - Githubissues

Major refactor of code:

Shedding old matplotlib plotting code and related notebooks since we're going to replace it with plotly eventually
Reorganizing utility functions, including geometric utilities and plotting, all into one place
Factoring out commonalities between projective and circular coordiantes into the parent EMCoords class to condense code and make it more readable
Beginning to setup code coverage and continuous integration tools

scikit-tda / DREiMac