Adjust Dispatcher's routing

Remove vestigial Dispatcher->action/()
Move 404/500 actions from Controller base class to DefaultController to better
 distinguish default error handling from custom error handling
Adjust Dispatcher->Act() to handle 404 routing
Improve handling of login redirect url

Adjust escaping to properly handle redirect URLs containing ampersand
Augment HTML5 login link with Javascript to capture #hash segment
Add document tail

New standard View var $_tail and hidden div as LAST element in body
 to allow injection of JS/CSS