Add log warning when native ssh executable is not found
Add log warning when native ssh executable is not found

mitchellh/vagrant,bryson/vagrant,PatrickLang/vagrant,chrisroberts/vagrant,taliesins/vagrant,PatrickLang/vagrant,chrisroberts/vagrant,mitchellh/vagrant,marxarelli/vagrant,bryson/vagrant,taliesins/vagrant,marxarelli/vagrant,PatrickLang/vagrant,mitchellh/vagrant,crashlytics/vagrant,sni/vagrant,marxarelli/vagrant,taliesins/vagrant,taliesins/vagrant,PatrickLang/vagrant,gitebra/vagrant,chrisroberts/vagrant,sni/vagrant,bryson/vagrant,sni/vagrant,gitebra/vagrant,bryson/vagrant,chrisroberts/vagrant,gitebra/vagrant,crashlytics/vagrant,marxarelli/vagrant,crashlytics/vagrant,gitebra/vagrant,crashlytics/vagrant,mitchellh/vagrant,sni/vagrant