Failure to launch dashboard with error about missing class methods

While attempting to launch the dashboard, failures are reported about
missing methods like:

2017-05-09 12:11:59.784107 NotImplementedError: The DeleteParameter
BatchAction class must have both action_past and action_present
methods.

I've added two two missing methods.

Change-Id: Ia841aedd62973d0bb52c1a6a82e1c9bd8dc9d47c

trove_dashboard/content/database_configurations/tables.py

@@ -42,6 +42,22 @@ class DeleteConfiguration(tables.DeleteAction):
     data_type_singular = _("Configuration Group")
     data_type_plural = _("Configuration Groups")
 
+    @staticmethod
+    def action_present(count):
+        return ungettext_lazy(
+            u"Delete Configuration Group",
+            u"Delete Configuration Groups",
+            count
+        )
+
+    @staticmethod
+    def action_past(count):
+        return ungettext_lazy(
+            u"Deleted Configuration Group",
+            u"Deleted Configuration Groups",
+            count
+        )
+
     def delete(self, request, obj_id):
         api.trove.configuration_delete(request, obj_id)
 
@@ -134,6 +150,22 @@ class DeleteParameter(tables.DeleteAction):
     data_type_singular = _("Parameter")
     data_type_plural = _("Parameters")
 
+    @staticmethod
+    def action_present(count):
+        return ungettext_lazy(
+            u"Delete Parameter",
+            u"Delete Parameters",
+            count
+        )
+
+    @staticmethod
+    def action_past(count):
+        return ungettext_lazy(
+            u"Deleted Parameter",
+            u"Deleted Parameters",
+            count
+        )
+
     def delete(self, request, obj_ids):
         configuration_id = self.table.kwargs['configuration_id']
         (config_param_manager