= routing: move 'complete with future' tests around
+ httpx: add ToResponseMarshaller.oneOf for negotiated marshalling from several (sub-)marshallers, refs #581
+ httpx: Unmarshaller.oneOf to create negotiating Unmarshaller, fixes #581
Merge pull request #598 from jrudolph/i/581/metamarshallers-for-content-type-negotiation

Fix 581 for now