`stopPropagation` to avoid possibility of multiple file dialogs.
Added Y.ArrayAssert.isUnique()
Build
Update isPromise for compatibility with A+ 1.1
Don't re-create callback lists. Resolves #571
Small cleanup and perf improvement

V8 benefits from properties of objects being defined during the objects
initialization, so add _result during the resolver's construction
Only change the resolver's status once
Deprecate getStatus
Add a debug message for unhandled rejections
Missing semicolon
Uncomment `testOpenFileSelect` unit test.
Uncomment `testOpenFileSelect` unit test.
Place `click` handler in the more correct `bindUI` method.
Can't get a BUTTON dom element s value attribute properly in IE7
Add src parameter to log calls
Do not return inside try...catch
Add HISTORY entry
Addition of `DOMContentLoaded` event.
Removal of `event-ready-base.js`.
Removal of `event-ready-base.js` from `event`'s build.
Use NAME in log's third argument