Ansys fork of pythonnet.

We will try to keep this up-to-date with pythonnet and upstream changes that might benefit the pythonnet community

Changes relative to pythonnet:

• Revert of #1240.
• Enum REPR #2239 <pythonnet/pythonnet#2239> is included in this release of version 3.0.2, but is unreleased in pythonnet
• Opt-into explicit interface wrapping, #19 <#19>. This opts into the behavior that became the default in #1240 if ToPythonAs<T> is explicitly used