[x3d-public] Moving away two language solutions for X3DJSAIL.

[John Carlson]

I've been planning to deprecate pythonSAI.  This is the python API that 
uses pyjnius to access X3DJSAIL.  This is because the web3d consortium 
has come out with their own SAI candidate x3d.py, which is much better 
documented and uses more features from X3DUOM.  Not only that, I don't 
think that pyjnius works on Linux very well!  What I plan on doing is 
moving my PythonSerializer.js towards using x3d.py.

In general, there's some dissatisfaction with using non-Java languages 
with X3DJSAIL.  Nashorn got tossed by Oracle, and the npm java package 
likely requires an old version of python for node-gyp.

The good news is, we're coming out with new, one-language solutions.  
Not only x3d.py, but there's X3DOM and X_ITE for JavaScript.   Also, the 
es6x3d project was started by me.  Es6x3d offers classes and new get/set 
methods compatible with es6. Meanwhile GraalVM is still around in the 
short term for Nashorn folks trying to migrate.  If you need a 
conversion from X3D JSON or X3D XML to a particular programming language 
or encoding and can't stomach XSLT, let me know!  I don't mind 
volunteering on non-X3D projects, but I prefer ASCII or UTF-8 encodings! 
I already have X3D JSON <-> STL and PLY -> X3D JSON in mini prototypes.  
Is anyone doing AMF yet?  Looks like there's a lot more interest in STL 
than AMF!

For my STL -> JSON project, does anyone have experience with inverseCSG 
or CSGNet?  Thanks! https://arxiv.org/pdf/1912.11393.pdf

John