2022-9-19

• BlueSky pypi package split into three packages: a source package (bluesky-simulator) and two data packages (bluesky-guidata and bluesky-simdata). Since BlueSky's data is big, but only changes rarely, putting it in separate packages saves pypi space and reduces download size for version updates of the code.
• Reduced size of source package.
• BlueSky resource access updated to provide multi-path access. When running from package, the $home/bluesky folder can now be used to provide additional data (plugins, scenarios, ...), or override package data (e.g., alternative navigation data). This works if the same folder structure is used (correct folders are created when bluesky is run for the first time)
• Fix backward compatibility with Python < 3.9 (using importlib_resources)