Consider making Predbat a Python package

[iainfogg]

@springfall2008 if the code was a Python package (or the bulk of it was) it would make it easily installable by pip, saving the need for manual installation code. It would also simplify using it in the various environments that you'd like to be able to run it, including in non-HA environments.

Happy to think about this, or you or someone else can, but thought it was worth logging.