Switch from containers/image to go-containerregistry (#140)

* Vendor changes for go-containerregistry switch.

* Manual changes for go-containerregistry switch.

The biggest change is refactoring the tarball unpacking.

* Pull more of container-diff out.

* More vendor removals.

* More unit tests.

vendor/github.com/Microsoft/hcsshim/getlayermountpath.go

@@ -1,55 +0,0 @@
-package hcsshim
-
-import (
-	"syscall"
-
-	"github.com/sirupsen/logrus"
-)
-
-// GetLayerMountPath will look for a mounted layer with the given id and return
-// the path at which that layer can be accessed.  This path may be a volume path
-// if the layer is a mounted read-write layer, otherwise it is expected to be the
-// folder path at which the layer is stored.
-func GetLayerMountPath(info DriverInfo, id string) (string, error) {
-	title := "hcsshim::GetLayerMountPath "
-	logrus.Debugf(title+"Flavour %d ID %s", info.Flavour, id)
-
-	// Convert info to API calling convention
-	infop, err := convertDriverInfo(info)
-	if err != nil {
-		logrus.Error(err)
-		return "", err
-	}
-
-	var mountPathLength uintptr
-	mountPathLength = 0
-
-	// Call the procedure itself.
-	logrus.Debugf("Calling proc (1)")
-	err = getLayerMountPath(&infop, id, &mountPathLength, nil)
-	if err != nil {
-		err = makeErrorf(err, title, "(first call) id=%s flavour=%d", id, info.Flavour)
-		logrus.Error(err)
-		return "", err
-	}
-
-	// Allocate a mount path of the returned length.
-	if mountPathLength == 0 {
-		return "", nil
-	}
-	mountPathp := make([]uint16, mountPathLength)
-	mountPathp[0] = 0
-
-	// Call the procedure again
-	logrus.Debugf("Calling proc (2)")
-	err = getLayerMountPath(&infop, id, &mountPathLength, &mountPathp[0])
-	if err != nil {
-		err = makeErrorf(err, title, "(second call) id=%s flavour=%d", id, info.Flavour)
-		logrus.Error(err)
-		return "", err
-	}
-
-	path := syscall.UTF16ToString(mountPathp[0:])
-	logrus.Debugf(title+"succeeded flavour=%d id=%s path=%s", info.Flavour, id, path)
-	return path, nil
-}