Develop Python Wrappers for IQTree2 as a Library

- pytest tests that can automate the IQTree2 library  
  - initially converting at least one of the pytest tests that automate IQTree2 by shelling out to it's executable
- command-line python app that can automate the IQTree2 library  
- Cogent3 plug-in that can automate the IQTree2 library  