Wrap output in thread when being called from within trap-context
Wrap output in thread when being called from within trap-context

This prevents a ThreadError exception being raised on sigint which
resulted in a stacktrace being dumped.

mitchellh/vagrant,sni/vagrant,chrisroberts/vagrant,gitebra/vagrant,mitchellh/vagrant,chrisroberts/vagrant,marxarelli/vagrant,chrisroberts/vagrant,sni/vagrant,gitebra/vagrant,mitchellh/vagrant,sni/vagrant,mitchellh/vagrant,gitebra/vagrant,marxarelli/vagrant,chrisroberts/vagrant,bryson/vagrant,bryson/vagrant,bryson/vagrant,marxarelli/vagrant,bryson/vagrant,marxarelli/vagrant,gitebra/vagrant,sni/vagrant