vendor: update go-mtree and image-spec

In order to fix a slight goof on the side of upstream (image-spec) we
have to add a patch that includes opencontainers/image-spec#460 (which
was _meant_ to be in v1.0.0-rc3 because the relevant spec change was
included).

Signed-off-by: Aleksa Sarai <[email protected]>

Author: cyphar

glide.lock

@@ -13,12 +13,12 @@ import:
   subpackages:
   - generate
 - package: github.com/opencontainers/image-spec
-  version: v1.0.0-rc2
+  version: v1.0.0-rc3
   subpackages:
   - specs-go
 - package: github.com/opencontainers/runtime-spec
   version: v1.0.0-rc2
   subpackages:
   - specs-go
 - package: github.com/vbatts/go-mtree
-  version: master
+  version: ~v0.3.0

glide.yaml

@@ -0,0 +1,27 @@
+From 6ac650626feb8f806af721c4a024b2d9bb360da5 Mon Sep 17 00:00:00 2001
+From: Lei Jitang <[email protected]>
+Date: Thu, 17 Nov 2016 14:04:59 +0800
+Subject: [PATCH 1/2] specs-go: add labels to config.go
+
+Signed-off-by: Lei Jitang <[email protected]>
+---
+ specs-go/v1/config.go | 3 +++
+ 1 file changed, 3 insertions(+)
+
+diff --git a/specs-go/v1/config.go b/specs-go/v1/config.go
+index d42383622695..894cc6cb70f5 100644
+--- a/specs-go/v1/config.go
++++ b/specs-go/v1/config.go
+@@ -45,6 +45,9 @@ type ImageConfig struct {
+ 
+ 	// WorkingDir sets the current working directory of the entrypoint process in the container.
+ 	WorkingDir string `json:"WorkingDir,omitempty"`
++
++	// Labels contains arbitrary metadata for the container.
++	Labels map[string]string `json:"labels,omitempty"`
+ }
+ 
+ // RootFS describes a layer content addresses
+-- 
+2.11.0
+

hack/imagespec-0001-specs-go-add-labels-to-config.go.patch

@@ -27,5 +27,14 @@ patch() {
 	command patch -d "$VENDOR/$project" -p1 <"$SCRIPTDIR/$patch"
 }
 
+# These are patches that I wrote as part of vbatts/go-mtree#96 (with a few
+# changes to port the code to using pkg/unpriv). I'm doubtful that this code
+# will ever be upstreamed -- at least not until pkg/unpriv is split into a
+# separate project.
 patch github.com/vbatts/go-mtree gomtree-0001-entries-prepend-all-hierarchies-with-keyword-metadat.patch
 patch github.com/vbatts/go-mtree gomtree-0002-walk-implement-unprivileged-walking.patch
+
+# Backport of opencontainers/image-spec#460. This patch wasn't included in
+# v1.0.0-rc3 even though the change to the specification was, resulting in a
+# mismatch. While upstream figures out a way to fix this, just patch it.
+patch github.com/opencontainers/image-spec imagespec-0001-specs-go-add-labels-to-config.go.patch