add dual listener when on a touch-enabled browser
build event-touch
Merge branch 'dev-3.x' into dual-listener
Merge branch 'dev-3.x' into dual-listener

Conflicts:
	build/event-touch/event-touch-coverage.js
event-tap now has preventDefault(), works on Android 4.0.x and on mouse/touch enabled devices.

event-tap got a bunch of modifications in this commit:
- Dual listener support! Listens to "touchstart mousedown", and based on which one is captured, sets up listeners for either "touchmove", "touchend", "touchcancel", OR the equivalent mouse events. Now, touch events obviously fire a corresponding mouse event, and I didn't want to have a heavy-handed event.preventDefault() in the code. To prevent the corresponding mouse/click events from firing `touchEnd()`, I set up a `needToCancel` boolean that is toggled once the first `touchstart/mousedown` is captured.

- e.preventDefault() works!  You can now do this:
```
    node.on('tap', function (e) {
      e.preventDefault();
      //do some stuff here...
    });
```
update unit tests to work with commit 9cbc2f6
add manual tap test
Don't break the back/forward cache. Fixes #959

Attaching an unload listener breaks the back/forward cache in modern
browsers, and is only necessary in old versions of IE that can leak
memory across pageviews if events aren't detached.
ButtonGroup.disable disables all child buttons / inputs
See #973
Bump version to 3.12.0pre
Merge branch 'dev-3.x' of github.com:yui/yui3 into dev-3.x
Merge branch 'dev-master' into dev-3.x
Merge branch 'event-bfcache' of git://github.com/rgrove/yui3 into dev-3.x
Build event.
Update Event history.
Merge branch 'button-group-disable' of git://github.com/asystance/yui3 into dev-3.x
Build button.
Merge branch 'dev-master' into dev-3.x
Merge branch 'dev-master' into dev-3.x
Build unbuild modules.