WIP: Added YueScript support

[bram-dingelstad]

It still needs a lot of work, but I wanted to update you on this. We've been talking on DM for a while, but this is the fruit of my labour thusfar.

Not that many changes, but it does allow the addition of a transpiled language as an addition to the project.

Some things I still need to do in order to be complete enough for merging:

• [ ] Make an automatic builder for YueScript shared library
• [ ] In case we don't want YueScript as a dependency: detect presence of yue.so and enable feature accordingly
• [ ] Throw appropriate errors for when there are syntax errors
• [ ] Use YueScript's native class / extend declaration to register as class_name and extends property
• [ ] Fix some tabbing issues

I'll leave some notes at specified code locations for more elaborate explanations.