Vendor containers/storage, update containers/image

Vendor containers/storage, and its dependencies github.com/pborman/uuid
and github.com/mistifyio/go-zfs, which we didn't already use.

Update the build Dockerfile to install their dependencies.

Add scriptlets that try to detect whether or not we need to use the
"libdm_no_deferred_remove" and/or "btrfs_noversion" build tags.

Signed-off-by: Nalin Dahyabhai <nalin@redhat.com>

vendor/github.com/containers/storage/pkg/mount/mount.go

@@ -0,0 +1,74 @@
+package mount
+
+import (
+	"time"
+)
+
+// GetMounts retrieves a list of mounts for the current running process.
+func GetMounts() ([]*Info, error) {
+	return parseMountTable()
+}
+
+// Mounted determines if a specified mountpoint has been mounted.
+// On Linux it looks at /proc/self/mountinfo and on Solaris at mnttab.
+func Mounted(mountpoint string) (bool, error) {
+	entries, err := parseMountTable()
+	if err != nil {
+		return false, err
+	}
+
+	// Search the table for the mountpoint
+	for _, e := range entries {
+		if e.Mountpoint == mountpoint {
+			return true, nil
+		}
+	}
+	return false, nil
+}
+
+// Mount will mount filesystem according to the specified configuration, on the
+// condition that the target path is *not* already mounted. Options must be
+// specified like the mount or fstab unix commands: "opt1=val1,opt2=val2". See
+// flags.go for supported option flags.
+func Mount(device, target, mType, options string) error {
+	flag, _ := parseOptions(options)
+	if flag&REMOUNT != REMOUNT {
+		if mounted, err := Mounted(target); err != nil || mounted {
+			return err
+		}
+	}
+	return ForceMount(device, target, mType, options)
+}
+
+// ForceMount will mount a filesystem according to the specified configuration,
+// *regardless* if the target path is not already mounted. Options must be
+// specified like the mount or fstab unix commands: "opt1=val1,opt2=val2". See
+// flags.go for supported option flags.
+func ForceMount(device, target, mType, options string) error {
+	flag, data := parseOptions(options)
+	if err := mount(device, target, mType, uintptr(flag), data); err != nil {
+		return err
+	}
+	return nil
+}
+
+// Unmount will unmount the target filesystem, so long as it is mounted.
+func Unmount(target string) error {
+	if mounted, err := Mounted(target); err != nil || !mounted {
+		return err
+	}
+	return ForceUnmount(target)
+}
+
+// ForceUnmount will force an unmount of the target filesystem, regardless if
+// it is mounted or not.
+func ForceUnmount(target string) (err error) {
+	// Simple retry logic for unmount
+	for i := 0; i < 10; i++ {
+		if err = unmount(target, 0); err == nil {
+			return nil
+		}
+		time.Sleep(100 * time.Millisecond)
+	}
+	return
+}