v0.4.1
- GUI and CLI prompts for upgrade through callback
- Add CLI flag to bypass upgrade warning
- Add set_version function to SQLiteBackend
- Add graceful_quit function to GUI to stop logging before quits
- Wrap all Freqlog init calls in try-except for graceful error logging
- Refactor ConfirmDialog in GUI to use MessageBox instead of Dialog
- Change bug TODOs into FIXMEs
- Misc. bugfixes