Notes for ES6 import support

[dead-claudia]

General API sketch:

• invoke.import(import.meta, mod, opts).then(...) = ES6 import
  • I can't do the magic wrapping I do for CommonJS, since I can't access the cache, much less modify it.
• Calling methods are just as normal.
• Requires library to be compiled to two separate targets (main and worker).
• Worker methods are loaded as modules and exported.
• Note: import isn't a valid variable binding, but it is a valid export name.
• Shouldn't require a major amount of work short of just re-implementing Node's ESM lookup algorithm.
• Optional loader hook that allows you to do import {...} from "worker.js#parallel" using the global pool. (easy)