2024.2.9.2: Merge pull request #127 from paulsaxe/main
Finalized the handling of the MOPAC executable:
- If ~/SEAMM/mopac.ini exists and it has the needed information, use it.
- Otherwise, try using the template in the data directory.
- If that doesn't work, see if the executable is in the path.
Also switched from deprecated pkg_resources package before it becomes an issue.