http support in TypeScript
This is an experiment to add native http:// support to TypeScript. When the resolver is asked to resolve an http(s):// module, we can download it to a cache and resolve to the path in cache. TypeScript should be able to read and typecheck against this file in cache.
TypeScript's APIs are all synchronous, but we can use node worker_threads to do asynchronous things behind a synchronous facade. So even though TypeScript expects the resolver to return synchronously, we can use a worker thread to download remote HTTP assets into cache.