Plug Memory Leaks

This Pull Request:

* Removes the return value of ```view.show()``` to suppress warnings.
* Removes the return values in the logger tests to suppress warnings.
* Has ```entry``` tear down the manager when the page closes the root class, which causes all workers to be destroyed.
* Adds a ```DEBUG_BACKREF``` field to the anonymous closure created by ```util.handleEvents``` so that you can see what object an event is attached to.
* Deletes a few references that were preventing data structures from being garbage collected because of outstanding event listeners.
All of the things in this block only make sense of there is a ```port``` defined. This stuff was getting hit in unit tests now that stuff is getting shut down more forcefully, so modules that we don't start up all the way (so they never create their port) will get told to close.