make loadLanguages method protected
add some structure and comments
simplify too detailed assertions
add plugin, controller, action to group_permissions migration
add new cache configs and change cache prefixes

- add core.group_permissions cache config
- add core.guardian_paths cache config
- change prefixes from boolean false to an empty string

Boolean false as cache prefix resulted in a cache clear error due to string comparisons in Cake's FileEngine cache.
Group hasMany GroupPermission
add new finder and supply missing App::uses statements
add backendPrefix instance variable
add Dashboard controller and make it the default login redirect
add conditional debug class to header
add empty check
append application name to title
add GroupPermissionFixture and refactor BackendAppControllerTest

refactor BackendAppControllerTest:
- add the new GroupPermissionFixture
- remove fake authenticator components and use real login instead
adjust tests to reflect 04aa58b018019c8be98c725a32ca17366f22bf49
add group config and fake group id option to _loginUser method
add WasabiNav class

This class is used to streamline event driven menu creation for the whole backend.
Priorities on primary and secondary menu items allow item injection further down the chain.
Guardian, Permissions and other adjustments

- add GuardianComponent (for public action authorization)
- add PermissionsController (manage all action specific group permissions) + index action + index.ctp + specific js functionality in script.js
- add spin.js v1.3 and jQuery Color v2.1.2 to plugins.js
- add spin.js jQuery plugin to scripts
- adjust CoreEvents to use the new WasabiNav Lib 6cc7030235cd5e83f90e466b837bd524ed236039 and load guest actions via a new event
- adjust BackendAppController to use the Guardian for permission checks, load menu items through WasabiNav and add permission checks to individual menu links
- adjust CHtmlHelper, NavigationHelper: implement Guardian permission checks
- adjust Users index.ctp: check permission on edit links
- adjust app.less: several form related fixes, small color adjustments on form errors, new permission styles
clear WasabiNav items on every test tearDown()