protobuf 3.4

[Maksimka79]

Hi!

Thank you very much for your work! It makes using grpc/protobuff on Windows really a lot easier.

Is there any chances in near future to get protobuff 3.4 working?
It seems not to compile out of the box, when i switching to the protobuff branch 3.4

It would be really hekpfull!

Thank you in advance!