Latest release in preparation from move away from PySimpleGUI

• Major refactor of the code structure to follow a more cookie-cutter like template
• Fixed some major bugs with regard to menu options not working due to callback issues and class declarations
• Noxfile added for future linting, formatting etc... but need to figure out about setting up arm runners for this to be most effective
• Removed the resizing option for the preview window as this did not serve much of a purpose and would end up blocking import desktop menu items which meant you could not close the window.
• Installation dependencies had to be updated due to recent breaking changes, e.g. PySimpleGUI had to be pinned to < v5 due to new paid version of the library.
• I have successfuly compile dearpygui on raspberty pi 32-bit OS which I will be moving towards in the next release.
• Added comprehensive installation guide, going through step-by-step how to setup a raspberry pifrom scratch to work with AstroPitography.