[keycloak-dev] Permission for client scopes

As scopes are often used for permissions in the applications themselves it would be useful to have a mechanism to grant a user access to a scope. For example if you have the scopes "photos:view" and "photos:edit" you would like only users that are permitted to use the photos application to be able to get those scopes in the token. One simple way of doing this would be to have a optional required role associated with a client scope. Then we can simply apply the client scopes for which the user has the required role.