Changes

tsk73 Admin User Draft
Adds several changes to register the role of an admin User. To be more
accurate:
-Adds role ADMIN in the enumerate Role.
-Creates a constructor for admins.
-Test the constructor.
-Updates users.xml and users-delete to include an admin
-Updates UsersDataset to reflect the changes.
-Updates UserAuthorizationEJBTest with a dummy check to avoid failing
due to the method getCurrentUser method because it only allows the USER
Role.