*: update grpc-gateway and its import paths

[gyuho]

No description provided.

[heyitsanthony]

does this fix the broken json unmarshaling?

[gyuho]

@heyitsanthony

Partially...

I have reliable way to reproduce. Found out it's an gogoproto issue or possibly we are generating the proto wrong way (gogofast instead of gofast). Once I figure it out, I will file an issue to gogoproto.

Either way we would need this update to support jsonpb from golang/protobuf.

[heyitsanthony]

@gyuho This is vendoring a lot of new dependencies. Did grpc-gateway add a bunch of new deps (particularly bad, all the golang.org/x/tools/godoc deps) or what?

[gyuho]

@heyitsanthony Yeah just noticed. I might have run godep wrong. Let me try again.

Thanks.

[gyuho]

@heyitsanthony @xiang90 PTAL.

Actually our grpc-gateway already supports golang/jsonpb, so this won't fix the json marshalling issue (I already filed an upstream issue to gogoproto).

This only updates to new grpc-gateway import path.

[xiang90]

lgtm