Bump runtime-spec/image-spec to v1.0.0-rc2

`v1.MediaTypeImageLayer` in latest image-spec has changed, need to be bumped up to the latest version.

This commit is only focused on bumping the vendored image-spec and runtime-spec to v1.0.0-rc2. `cobra` and `pflag` doesn't tag releases, so I'm pinning this at our currently-vendored commit. I'm not aware of any reason we can't advance this to a later pflag commit, but haven't done enough research to say for sure.

Signed-off-by: Ye Yin <[email protected]>

Author: hustcat

glide.lock

@@ -1,14 +1,17 @@
 package: github.com/opencontainers/image-tools
 import:
 - package: github.com/opencontainers/image-spec
-  version: 7e6e2f76d6a11cdcb3f3e334e3f12179a0f37dad
+  version: v1.0.0-rc2
   subpackages:
   - schema
   - specs-go/v1
 - package: github.com/opencontainers/runtime-spec
-  version: ~1.0.0-rc1
+  version: v1.0.0-rc2
   subpackages:
   - specs-go
 - package: github.com/pkg/errors
   version: ~0.7.1
 - package: github.com/spf13/cobra
+  version: 9c28e4bbd74e5c3ed7aacbc552b2cab7cfdfe744
+- package: github.com/spf13/pflag
+  version: 7b17cc4658ef5ca157b986ea5c0b43af7938532b

glide.yaml

@@ -116,6 +116,7 @@ func (c *config) runtimeSpec(rootfs string) (*specs.Spec, error) {
 	swap := uint64(c.Config.MemorySwap)
 	shares := uint64(c.Config.CPUShares)
 
+	s.Linux = &specs.Linux{}
 	s.Linux.Resources = &specs.Resources{
 		CPU: &specs.CPU{
 			Shares: &shares,

image/config.go

@@ -103,7 +103,7 @@ var (
     "layers": [
         {
             "digest": "<layer_digest>",
-            "mediaType": "application/vnd.oci.image.layer.tar+gzip",
+            "mediaType": "application/vnd.oci.image.layer.v1.tar+gzip",
             "size": <layer_size>
         }
     ],

image/image_test.go

@@ -108,7 +108,7 @@ func TestUnpackLayer(t *testing.T) {
 
 	testManifest := manifest{
 		Layers: []descriptor{descriptor{
-			MediaType: "application/vnd.oci.image.layer.tar+gzip",
+			MediaType: "application/vnd.oci.image.layer.v1.tar+gzip",
 			Digest:    fmt.Sprintf("sha256:%s", fmt.Sprintf("%x", h.Sum(nil))),
 		}},
 	}