Add TypeScript?

[Pandawan]

So idk if you really need it since you seem to be doing everything in JS, but I've rewritten ent-comp in TypeScript. I could submit a Pull Request if you wanted to add it in.

I've also added/modified some things, so it might not be the best idea to merge it as is. For example, I removed multi-components because I thought that you can just have array inside the component's state (and they were forcing me to check for Array.isArray every time due to TypeScript's strict typing nature). I've also upgraded everything to ES modules, added cleaner JSDoc, and added some extra functionality like getAllComponents().

So yeah, if you want to incorporate some/all of the new stuff I can make a pull request, if not, that's totally fine.