Add Versionable.detach() for creating a copy of a model. See #68
Add Versionable.detach() for creating a copy of a model. See #68

pretix/cleanerversion,swisscom/cleanerversion,anfema/cleanerversion,swisscom/cleanerversion,swisscom/cleanerversion,anfema/cleanerversion,anfema/cleanerversion,pretix/cleanerversion,pretix/cleanerversion