Move deps from _workspace/ to vendor/

godep restore
pushd $GOPATH/src/github.com/appc/spec
git co master
popd
go get go4.org/errorutil
rm -rf Godeps
godep save ./...
git add vendor
git add -f $(git ls-files --other vendor/)
git co -- Godeps/LICENSES Godeps/.license_file_state Godeps/OWNERS

vendor/github.com/coreos/pkg/httputil/README.md

@@ -0,0 +1,13 @@
+httputil
+====
+
+Common code for dealing with HTTP.
+
+Includes:
+
+* Code for returning JSON responses.
+
+### Documentation
+
+Visit the docs on [gopkgdoc](http://godoc.org/github.com/coreos/pkg/httputil)
+

vendor/github.com/coreos/pkg/httputil/json.go

@@ -0,0 +1,27 @@
+package httputil
+
+import (
+	"encoding/json"
+	"net/http"
+)
+
+const (
+	JSONContentType = "application/json"
+)
+
+func WriteJSONResponse(w http.ResponseWriter, code int, resp interface{}) error {
+	enc, err := json.Marshal(resp)
+	if err != nil {
+		w.WriteHeader(http.StatusInternalServerError)
+		return err
+	}
+
+	w.Header().Set("Content-Type", JSONContentType)
+	w.WriteHeader(code)
+
+	_, err = w.Write(enc)
+	if err != nil {
+		return err
+	}
+	return nil
+}