Only show events w/ descriptions in EventPalette

Also, auto-generate human readable event name in editor. This is a good example of how we could do this automatically for some kind of `onCommand`, `command`, `onInteractiveEvent` method that combines the event name, documentation string, and handler in one shot.

src/stdlib/underscore-extensions.coffee

@@ -51,3 +51,14 @@ _.mixin
     # even though only some strictly require it when inside of []
     regex = RegExp('[' + specials.join('\\') + ']', 'g')
     string.replace(regex, "\\$&");
+
+  humanizeEventName: (eventName) ->
+    if /:/.test(eventName)
+      [namespace, name] = eventName.split(':')
+      return "#{@humanizeEventName(namespace)}: #{@humanizeEventName(name)}"
+
+    words = eventName.split('-')
+    words.map(_.capitalize).join(' ')
+
+  capitalize: (word) ->
+    word[0].toUpperCase() + word[1..]