Imports of package graphtest

PathSynopsis
github.com/dotcloud/docker/daemon/graphdriver
io/ioutilPackage ioutil implements some I/O utility functions.
osPackage os provides a platform-independent interface to operating system functionality.
pathPackage path implements utility routines for manipulating slash-separated paths.
syscallPackage syscall contains an interface to the low-level operating system primitives.
testingPackage testing provides support for automated testing of Go packages.