Exploring ways to allow Optional dependencies (#1079)

* Enable optional dependencies. Starting with pptx.
* Fix CLI tests.... have them install [all]
* Added .docx to optional dependencies
* Reuse error messages for missing dependencies.
* Added xlsx and xls
* Added pdfs
* Added Ole files.
* Updated READMEs, and finished remaining feature-categories.
* Move OpenAI to hatch-test environment.