message: Add fb app secret prood to insights api
diff: @@ -934,6 +934,10 @@ function Facebookbot(configuration) {
  get_insights: function(metrics, since, until, cb) {
  var uri = 'https://' + api_host + '/' + api_version + '/me/insights?access_token=' + configuration.access_token;
  + if (facebook_botkit.config.require_appsecret_proof) {
  + uri += '&appsecret_proof=' + appsecret_proof;
  + }
  +
  if (metrics) {
  if (typeof(metrics) == 'string') {
  uri += '&metric=' + metrics;
  