Build from CommonJS source.

- Uses r.js RequireJS optimizer to build release/q.amd.js.
- Creates a temp file with `window.Q = require("./q");` and browserifies that to produce release/q.js.
- Minifies both to produce release/q.min.js and release/q.amd.min.js.
- Browser spec runner uses release/q.js.
Introduce ASAP dependency
Remove shims
No longer checking in build products
Preliminary change log update