add VERSION const as p5.VERSION

[micuat]

continues from #5107 and resolves #2525

• npm run lint passes
• [Inline documentation] is included / updated
• [Unit tests] are included / updated

I kept both p5.VERSION and p5.prototype.VERSION but not sure if we keep both or we just use the former so that it will never be exposed to global scope (no sketch=>sketch.VERSION in case of instance). Whichever it is, the new implementation (p5.VERSION) should have the priority as it has an advantage that it can be referenced without instantiation.

[outofambit]

hey @micuat, just checking in on this, I'd love to get this merged soon. are you still interested in working on this?

it looks like the only thing left is a decision on the prototype vs instance question above? I think it's probably good to have both. If we only use p5.VERSION, I think that would mean it wouldn't be available in the web editor (unless you this), which i think is worth preserving. open to other opinions, too!

Oh we need docs too! I can help with that if you'd like.

[micuat]

sure! I agree that it should be accessible both ways. Do you think it still needs an edit or is ready for review? I don't think I have access to a build environment / have time to test it right now, so I appreciate if anyone can test it (and edit it if needed).

[outofambit]

thanks @micuat! i tested locally and wrote some unit tests to be extra safe. merging now!