Comment 2 for bug 1294175

Regarding to "Also there should be some kind of mechanism to reject requests coming to manager, if they refer to failed plugin." At this moment in the code, if no plugin is registered for a particular resource type, some exceptions are raised: https://github.com/stackforge/climate/blob/master/climate/manager/service.py#L362
Are those exceptions enough or you prefer a new exception that tells explicitly that the resource type is rejected because the plugin fail during the initialization?