func (m *Manifest) SetUser(user string) error {
	if user == "" {
		return fmt.Errorf("user cannot be empty")
	}
	if m.manifest.App == nil {
		m.manifest.App = newManifestApp()
	}
	m.manifest.App.User = user
	return m.save()
}
SetUser sets the user the pod will run as in the untarred ACI stored at
a.CurrentImagePath.
package appc
import (
	"fmt"
)