Document Common Use Cases / "Recipes"

[daedalus28]

This ticket is about adding a section to readme that demonstrates common use cases (aka "recipes") of things that might not be obvious but are sufficiently handled by the current api (and so don't warrant adding anything to the API).

Some quick examples:

• Search button use cases: handled by autoUpdate: false + triggerUpdate action on a button
• Kicking off searches with referesh after load
• Leveraging triggerUpdate to force validation/hasValue on freshly instantiated trees
• Blocking blank searches by checking has value after triggerUpdate before refresh