Use go-winio tar-application code instead of our own

applyFunc now takes an io.Reader instead of a tar.Reader because I'm
trying to mirror the API of the not-yet-exposed implementation of this
same behaviour in github.com/Microsoft/hcsshim/internal/ociwclayer,
with an eye to later moving to that implementation it is ever exposed.

Signed-off-by: Paul "TBBle" Hampson <Paul.Hampson@Pobox.com>

archive/tar_opts.go

@@ -19,6 +19,7 @@ package archive
 import (
 	"archive/tar"
 	"context"
+	"io"
 )
 
 // ApplyOptions provides additional options for an Apply operation
@@ -27,7 +28,7 @@ type ApplyOptions struct {
 	ConvertWhiteout ConvertWhiteout // Convert whiteout files
 	Parents         []string        // Parent directories to handle inherited attributes without CoW
 
-	applyFunc func(context.Context, string, *tar.Reader, ApplyOptions) (int64, error)
+	applyFunc func(context.Context, string, io.Reader, ApplyOptions) (int64, error)
 }
 
 // ApplyOpt allows setting mutable archive apply properties on creation