Minor tweaks to circles demo. Deprecate *On methods

The *On methods will be removed in favor of setting scheduler upon stream creation.
Add fromEventWhere with filtering predicate
Merge pull request #35 from cujojs/add-from-event-where

Add fromEventWhere with filtering predicate
Update example to use rest.js 1.2, simplify
Add README for running examples
Add drag-n-drop behavior switching example
Add initial API docs.

Includes TOC and docs for creating and building streams.  Still much
more to write.