Remove mandatory dependency on node

[KOLANICH]

Also some prereq fixes.

Fixes: #3

[fateshelled]

Thanks for pull request.
But please write an explanation. Why do you want to exclude node.js?

[KOLANICH]

1. Its ecosystem has bad packaging practices.
2. The code written for node bundled with this lib is mostly redudndant. In the rewrite into python I got rid of most of it. If we eliminate node completely (by now I have kept that code, and allowed a user to choose, but it has some issues related to subprocessing) and the abstraction layer around a dict, we can get rid of even more, I guess the whole Netron-derived code can be excluded.
3. The redundant code is too large to audit and auditing it is unneeded cognitive load.
4. Requiring Node.js for a python package is ridiculous.
5. Managing a subprocess is additional burden

Also please note: this PR has some other commits solving some other issues (after they are landed and after we get the deps into Pypi, you can publish a pypi package), but I guess they won't properly commute with the commit of denodeing, so everything is bundled.

[fateshelled]

I do not intend to make a python package.
Do what you want with your own repository.