Namespace is not needed

We should be able to parse out the Path from the URL and use that as the
namespace.

meta.go

@@ -10,7 +10,6 @@ type Meta struct {
 	Name        Name    `json:"name"`
 	Version     Version `json:"version"`
 	Description string  `json:"description"`
-	Namespace   string  `json:"namespace"`
 
 	Remote url.URL `json:"remote"`
 }

meta_test.go

@@ -23,16 +23,6 @@ func TestValid(t *testing.T) {
 			},
 			ok: true,
 		},
-		{
-			label: "valid with namespace",
-			m: Meta{
-				Name:        "heat",
-				Version:     "1.1.0",
-				Description: "some description",
-				Namespace:   "some/namespace",
-			},
-			ok: true,
-		},
 		{
 			label: "missing name",
 			m: Meta{
@@ -78,7 +68,6 @@ func TestJsonRoundTrip(t *testing.T) {
 		Name:        "heat",
 		Version:     "1.1.0",
 		Description: "make heat using cpus",
-		Namespace:   "/darwin/amd64",
 	}
 
 	buf := &bytes.Buffer{}