Check name config option with respond_to?
Check name config option with respond_to?

Prior to this commit, the check used to look for the config option
`name` in a provisioner config would accidentally create a "DummyConfig"
based on how vagrant handles missing config options. This commit fixes
that by instead using the `respond_to?` method to check for the
existance of the config option name.

marxarelli/vagrant,mitchellh/vagrant,chrisroberts/vagrant,sni/vagrant,sni/vagrant,mitchellh/vagrant,chrisroberts/vagrant,marxarelli/vagrant,marxarelli/vagrant,sni/vagrant,marxarelli/vagrant,chrisroberts/vagrant,sni/vagrant,chrisroberts/vagrant,mitchellh/vagrant,mitchellh/vagrant