Need docs for eventDelegates block

[ebidel]

Adds event listeners to the host element. Keys are event names to listen for. Values are the callback:

eventDelegates: {
  up: 'onTap',
  down: 'onTap'
},
onTap: function(e, detail, sender) {
  ...
}

@sjmiles, is this the imperative equivalent of adding on-* to polymer-element?...similar to the publish and the attributes attribute?

[sjmiles]

Yes, exactly that.

[arthurevans]

This has been open way too long, I know.

I suggested it to @marycampione as a good starter bug to get used to working with our repo.