Imports of package system

PathSynopsis
github.com/containerd/continuity/fs
github.com/pkg/errorsPackage errors provides simple error handling primitives.
io/fsPackage fs defines basic interfaces to a file system.
pathPackage path implements utility routines for manipulating slash-separated paths.
path/filepathPackage filepath implements utility routines for manipulating filename paths in a way compatible with the target operating system-defined file paths.
stringsPackage strings implements simple functions to manipulate UTF-8 encoded strings.
syscallPackage syscall contains an interface to the low-level operating system primitives.
timePackage time provides functionality for measuring and displaying time.