Imports of testfiles command

PathSynopsis
github.com/docker/docker/pkg/signal
github.com/sirupsen/logrusPackage logrus is a structured logger for Go, completely API compatible with the standard library logger.
osPackage os provides a platform-independent interface to operating system functionality.
syscallPackage syscall contains an interface to the low-level operating system primitives.
timePackage time provides functionality for measuring and displaying time.