Collect memberof information for sudo commands.

We weren't searching the cn=sudo container so all members of a
sudocmdgroup looked indirect.

Add a label for sudo command groups.

Update the tests to include verifying that membership is done
properly.

ticket 1003

ipalib/plugins/sudocmd.py

@@ -55,8 +55,11 @@ class sudocmd(LDAPObject):
         'sudocmd', 'description',
     ]
     default_attributes = [
-        'sudocmd', 'description',
+        'sudocmd', 'description', 'memberof',
     ]
+    attribute_members = {
+        'memberof': ['sudocmdgroup'],
+    }
     uuid_attribute = 'ipauniqueid'
     label = _('SUDO Commands')