Specify encoding on file open

[goneall]

This allows the spec-parser to be run on windows where the default encoding is not UTF-8.

Also updated the .gitignore to ignore any venv folders

[zvr]

Do we really have non-ASCII input?

[goneall]

Do we really have non-ASCII input?

Apparently - I got an exception running spec-parser on Windows.

It tripped on spdx-3-model\model\Core\Properties\dataLicense.md

[zvr]

OK, I've created spdx/spdx-3-model#476 to fix this couple of quotes.

[goneall]

OK, I've created spdx/spdx-3-model#476 to fix this couple of quotes.

Reviewed it - we can merge it after a second review (even though I don't think anyone will complain if it was merged sooner)

Should we also merge this? Alternatively, we should document that you can only use ascii characters and verify it as part of the CI.

[zvr]

You know what I think: any time spent documenting spec parser is time lost of actually doing work on SPDX model and spec... So, it's faster to merge this one.

I did like the incidental fact that it was serving as a check about all-ASCII input, but I guess I can manually check once in a while.