Improve support for Controllers to be placed in sub-folders/packages.

Add support for placing controllers in sub-folders/packages within the controllers folder so you can keep related controllers together, create more structured urls and make path based url security easier?

For example:

\grails-app\controllers\SiteController.groovy -> http://localhost:8080/sample/site
\grails-app\controllers\admin\UserController.groovy -> http://localhost:8080/sample/admin/user
\grails-app\controllers\admin\RoleController.groovy -> http://localhost:8080/sample/admin/role

And views would obviously have to follow the package structure of their controller:

\grails-app\views\admin\user\show.gsp