Python infrastructure improvements

[rafmudaf]

Python infrastructure improvements

This pull request makes some changes to the Python infrastructure in OpenFAST. It includes #2680 from @faisal-bhuiyan (merged into another branch) which brought a major refactoring of aerodyn_inflow_library.py and some of the Python infrastructure in r-test. Additionally, I've consolidated the existing Python interfaces (aerodyn_inflow, inflow wind, hydrodyn, moordyn, fastlib) into a pip-installable package called OpynFAST 😜 .

While this pull request is relatively small in scope, it sets up additional changes to the Python infrastructure in the future. Currently, there is a ton of boilerplate Python code in the OpenFAST repository. In an effort to make what exist more reusable, I wanted to start migrating it into a pip-installable package that can be used like below instead of having to manually include a variety of paths:

from OpynFAST import fast

fast.init()
fast.sim()
fast.end()

The long term hope is that this package can evolve into a useful interface to drive OpenFAST modules. The scope here is distinct from openfast_io though closely related.

[rafmudaf]

@mayankchetan I've renamed the library to pyOpenFAST from OpynFAST