Echo JS 0.11.0

Relatively thin article, mostly on how to use ServiceWorker for caching/offline use... other things to look into as a followup are online/offline detection and local-remote data sources.  May also want to look into pouchdb and other options for data syncing.

Aside: haven't looked into it... but have wanted to try to get a couchdb setup or proxy where there are read-only data sources that cache locally, and read/write data sources that sync per-user via couch/pouch.  Of course there's also other potential issues depending on use case.