public function revokePermission($id, $permission_id)
 {
     $role = Role::find($id);
     $permission = Permission::find($permission_id);
     $role->revokePermission($permission);
     return redirect()->back();
 }
 public function getPermissions()
 {
     return Permission::with('roles')->get();
 }
 public function destroy($id)
 {
     Permission::find($id)->delete();
     return redirect()->route('admin.permissions.index');
 }