Add Python Data Types to functions

[dragonejt]

In my opinion, types in Python make it a lot easier for people who use this package to understand what they need to supply for a certain function, build plugins, etc because the requirements for what types of data you need to have are more clear. It's a form of code documentation that requires a little less effort than full docstrings or wikis.

Here is an article about them: https://www.geeksforgeeks.org/python-data-types/

If we want data types for the OnAIR package, I can get started on a PR to add types to our functions.

[dragonejt]

Working on this for the data handlers first, will submit a PR soon