- use localizations for menubar
- bump AutoGGUF version to v2.0.0
- rename imports_and_globals.py to globals.py
- reformat code
- use file select for Merge/Split GGUF functions
- move general functions verify_gguf and process_args to globals.py
- create Plugins class for extensibility
- add more configuration options for AUTOGGUF_MODEL_DIR_NAME, AUTOGGUF_OUTPUT_DIR_NAME, and AUTOGGUF_RESIZE_FACTOR (these get created on startup)
- move some UI helper funtions out of AutoGGUF.py and into ui_update and Ta
- optimize imports for utility classes
- fix some missing imports