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/mesos/mesos-go/auth/callback/interface.go

@@ -0,0 +1,28 @@
+package callback
+
+import (
+	"fmt"
+)
+
+type Unsupported struct {
+	Callback Interface
+}
+
+func (uc *Unsupported) Error() string {
+	return fmt.Sprintf("Unsupported callback <%T>: %v", uc.Callback, uc.Callback)
+}
+
+type Interface interface {
+	// marker interface
+}
+
+type Handler interface {
+	// may return an Unsupported error on failure
+	Handle(callbacks ...Interface) error
+}
+
+type HandlerFunc func(callbacks ...Interface) error
+
+func (f HandlerFunc) Handle(callbacks ...Interface) error {
+	return f(callbacks...)
+}