Rename AST utils file.
Get Caches, via Map & AsyncMap, closer to spec.
Release v0.1.5.
Be more informative about errors & happenings.
Merge pull request #37 from ahume/master

Throw error if any request in importScripts() fail.
Release v0.1.6.
Do Cache, ResponsePromise and fetch properly.

- Remove _Requester
- Follow ES6 spec with Map better
- Add stubs for cache persistence methods
Pass raw glob URL to be used for ServiceWorker.registration prop.