def registered_script_path(cloud_name)
      cloud_script_path = registered_type(cloud_name)
      raise UnknownCloud.new("Unknown cloud: #{cloud_name}") unless cloud_script_path
      return cloud_script_path
    end
def registered_script_path(cloud_name)
      cloud_script_path = registered_type(cloud_name)
      raise UnknownCloud.new("Unknown cloud: #{cloud_name}") unless cloud_script_path
      return cloud_script_path
    end
Gets the path to the script describing a cloud.

 === Parameters
 cloud_name(String):: a registered_type cloud name

 === Return
 cloud_script_path(String):: path to script used to describe cloud on creation

 === Raise
 UnknownCloud:: on error