def audiences(project_id)
      raise OptimizelyError::NoProjectID, "A Project ID is required to retrieve audiences." if project_id.nil?

      response = self.get("projects/#{project_id}/audiences")
      response.collect { |audience_json| Audience.new(audience_json) }
    end
def audiences(project_id)
      raise OptimizelyError::NoProjectID, "A Project ID is required to retrieve audiences." if project_id.nil?

      response = self.get("projects/#{project_id}/audiences")
      response.collect { |audience_json| Audience.new(audience_json) }
    end
Returns the list of audiences for a specified project.

 == Usage
  optimizely = Optimizely.new({ api_token: 'oauth2_token' })
  audiences = optimizely.audiences(12345) # Look up all audiences for a project.