[protobuf] Recursion support in Protobuf-net

Would it be possible to support recursive graphs in protobuf-net, as a implementation-specific custom message extension? For example, if protobuf-net could automatically insert an optional int32 uniqueID = 1000 field in to each message, it could store an auto-generated unique identifier for each

[protobuf] Support for generic surrogates, eg. QueueT

I've made a small modification to add support for user-specified surrogate classes for generic types, via the same mechanism as KeyValueSurrogate. This will let you serialize generic types such as QueueT by defining and registering a [ProtoContract] surrogate type, QueueSurrogateT. I thought I'd