Imports of http2 command

PathSynopsis
flagPackage flag implements command-line flag parsing.
golang.org/x/net/contextPackage context defines the Context type, which carries deadlines, cancellation signals, and other request-scoped values across API boundaries and between processes.
google.golang.org/grpcPackage grpc implements an RPC system called gRPC.
google.golang.org/grpc/codesPackage codes defines the canonical error codes used by gRPC.
google.golang.org/grpc/grpclogPackage grpclog defines logging for grpc.
google.golang.org/grpc/interopPackage interop contains functions used by interop client/server.
google.golang.org/grpc/interop/grpc_testing
google.golang.org/grpc/statusPackage status implements errors returned by gRPC.
netPackage net provides a portable interface for network I/O, including TCP/IP, UDP, domain name resolution, and Unix domain sockets.
strconvPackage strconv implements conversions to and from string representations of basic data types.
syncPackage sync provides basic synchronization primitives such as mutual exclusion locks.
timePackage time provides functionality for measuring and displaying time.