Closes https://github.com/denoland/deno/issues/27229.
TODO:
- [x] Tests
- [x] Make some changes to `deno_cache_dir` so we can get the paths for
the local http cache
- [x] Right now this leaves the node modules setup cache in an incorrect
state (removes the symlinks, but doesn't update the setup cache)
- [ ] ~~Handle code cache and other sqlite caches?~~
