Migrate index.html example to raf@1.0.0

raf was split in two (raf and raf-stream) before the 1.0.0 release. raf is now
the actual polyfill, while raf-stream is an event emitter which wraps raf.
Merge pull request #49 from CMTegner/migrate-to-raf-1.0

Migrate index.html example to raf@1.0.0