Add http transport for server to Go lib

There is a lack of http transport for server in Go lib, so the server could not communicate with client running http transport, e.g., client runs the Go code lib/go/thrift/http_client.go, or C++ async client which usually runs along with libevent and http transport.

Some code similar to lib/cpp/src/thrift/transport/THttpTransport.cpp needs to be added to Go lib, in order to run a server written in Go to communicate with these http transport client.