Modularize code for paradigm generation, with a clean interface layer

[aarppe]

In order to allow for the independent use of paradigm generation, organize the code into a separate module/package with a clear interface through which the paradigm generation can be invoked.

[aarppe]

@eddieantonio To what extent is this already done? Since we have implemented the pane-based solution, but is it primarily that we have a generic well-defined specification for paradigms, but the relevant code hasn't yet been separated fully?

[eddieantonio]

@aarppe the Python core is pretty much its own, self-contained package, namely CreeDictionary.CreeDictionary.paradigm.

It would be about a two week's worth of work to extract this and make an app that only loads and shows arbitrary paradigms.

[nienna73]

The backend paradigm generation has been pulled out into its own package available here: https://pypi.org/project/paradigm-panes/

This package does nothing with the front-end.