new "image" mount type

Add a new "image" mount type to `--mount`.  The source of the mount is
the name or ID of an image.  The destination is the path inside the
container.  Image mounts further support an optional `rw,readwrite`
parameter which if set to "true" will yield the mount writable inside
the container.  Note that no changes are propagated to the image mount
on the host (which in any case is read only).

Mounts are overlay mounts.  To support read-only overlay mounts, vendor
a non-release version of Buildah.

Signed-off-by: Valentin Rothberg <rothberg@redhat.com>

vendor/github.com/fsouza/go-dockerclient/container_rename.go

@@ -0,0 +1,33 @@
+package docker
+
+import (
+	"context"
+	"fmt"
+	"net/http"
+)
+
+// RenameContainerOptions specify parameters to the RenameContainer function.
+//
+// See https://goo.gl/46inai for more details.
+type RenameContainerOptions struct {
+	// ID of container to rename
+	ID string `qs:"-"`
+
+	// New name
+	Name    string `json:"name,omitempty" yaml:"name,omitempty"`
+	Context context.Context
+}
+
+// RenameContainer updates and existing containers name
+//
+// See https://goo.gl/46inai for more details.
+func (c *Client) RenameContainer(opts RenameContainerOptions) error {
+	resp, err := c.do(http.MethodPost, fmt.Sprintf("/containers/"+opts.ID+"/rename?%s", queryString(opts)), doOptions{
+		context: opts.Context,
+	})
+	if err != nil {
+		return err
+	}
+	resp.Body.Close()
+	return nil
+}