Feature/logging via class
In order to allow for logging using the built-in Flask logger, the best course of action was to refactor the functions into a class. This led to some other architectural changes, including making API calls using the credentials that are passed in when the app starts instead of credentials entered on a page. I've also updated all .format() functions to use f-strings instead, making the minimum Python version for SL1ther 3.6.
There are also numerous formatting changes in order to help pass Flake8 style requirements.