Refactorings and adding pydantic

[skuam]

Hey, I found your project and that was exactly what I needed, but it rather crude form and the overall quality of code seemed not satisfactory to me. So I fixed up the code and made it a bit more clear and general. Overall functionality remains unchanged. Mainly, I changed the way you call to do it through class, so there is no global GLOBIT variable and it is more configurable and put all flying dictionaries with data into proper Pydantic classes, so it is easier for any application to ingest the data. Feel free to either disregard this pull request or merge it if you like the changes.