Imports of dmverity-vhd command

PathSynopsis
archive/tarPackage tar implements access to tar archives.
bytesPackage bytes implements functions for the manipulation of byte slices.
contextPackage context defines the Context type, which carries deadlines, cancellation signals, and other request-scoped values across API boundaries and between processes.
encoding/jsonPackage json implements encoding and decoding of JSON as defined in RFC 7159.
errorsPackage errors implements functions to manipulate errors.
fmtPackage fmt implements formatted I/O with functions analogous to C's printf and scanf.
github.com/Microsoft/hcsshim/ext4/dmverity
github.com/Microsoft/hcsshim/ext4/tar2ext4
github.com/docker/docker/clientPackage client is a Go client for the Docker Engine API.
github.com/google/go-containerregistry/pkg/authnPackage authn defines different methods of authentication for talking to a container registry.
github.com/google/go-containerregistry/pkg/namePackage name defines structured types for representing image references.
github.com/google/go-containerregistry/pkg/v1/remotePackage remote provides facilities for reading/writing v1.Images from/to a remote image registry.
github.com/sirupsen/logrusPackage logrus is a structured logger for Go, completely API compatible with the standard library logger.
github.com/urfave/cliPackage cli provides a minimal framework for creating and organizing command line Go applications.
ioPackage io provides basic interfaces to I/O primitives.
osPackage os provides a platform-independent interface to operating system functionality.
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.