Doc changes

/to @bajtos @al
As previously discussed, this PR:
 - Removes the README content from the API docs.  Only the JSdoc remains in the API doc (except see below).
 - Separates display of API doc into Node and Browser.  To workaround a limitation of strong-docs (no text above a method signature), I added two short md files to indicate the canonical usage, and changed the @header tag in the source files accordingly.
- Removes most of the README content that was moved to Confluence and linked to Confluence doc.  Note this doc is not yet published since 2.0 has not been released.  That means this link will not work for the public yet.