Fix Config.Cpuset from API < 1.20

Signed-off-by: Antonio Murdaca <amurdaca@redhat.com>

api/types/versions/v1p19/types.go

@@ -24,5 +24,5 @@ type ContainerConfig struct {
 	Memory       int64
 	MemorySwap   int64
 	CPUShares    int64  `json:"CpuShares"`
-	CPUSet       string `json:"CpuSet"`
+	CPUSet       string `json:"Cpuset"`
 }

api/types/versions/v1p20/types.go

@@ -16,7 +16,8 @@ type ContainerJSON struct {
 // ContainerConfig is a backcompatibility struct used in ContainerJSON for the API 1.20
 type ContainerConfig struct {
 	*runconfig.Config
-	// backward compatibility, it lives now in HostConfig
+
+	// backward compatibility, they now live in HostConfig
 	VolumeDriver string
 }