zipkin-related build issue

[rajendrarusmana]

I got this error while running go build when trying to run the helloworld example

source.golabs.io/growth/actor-model-demo/vendor/github.com/openzipkin/zipkin-go-opentracing/_thrift/gen-go/scribe

vendor/github.com/openzipkin/zipkin-go-opentracing/_thrift/gen-go/scribe/scribe.go:101:15: cannot assign 1 values to 2 variables

vendor/github.com/openzipkin/zipkin-go-opentracing/_thrift/gen-go/scribe/scribe.go:147:28: cannot use scribeProcessorLog literal (type *scribeProcessorLog) as type thrift.TProcessorFunction in assignment:
*scribeProcessorLog does not implement thrift.TProcessorFunction (wrong type for Process method)
have Process(int32, thrift.TProtocol, thrift.TProtocol) (bool, thrift.TException)
want Process(context.Context, int32, thrift.TProtocol, thrift.TProtocol) (bool, thrift.TException)

vendor/github.com/openzipkin/zipkin-go-opentracing/_thrift/gen-go/scribe/scribe.go:157:27: not enough arguments in call to processor.Process
have (int32, thrift.TProtocol, thrift.TProtocol)
want (context.Context, int32, thrift.TProtocol, thrift.TProtocol)