added deprecate message

Author: christkv

lib/db.js

@@ -658,6 +658,7 @@ var evaluate = function(self, code, parameters, options, callback) {
  * @param {object} [options=null] Optional settings.
  * @param {boolean} [options.nolock=false] Tell MongoDB not to block on the evaulation of the javascript.
  * @param {Db~resultCallback} [callback] The results callback
+ * @deprecated Eval is deprecated on MongoDB 3.2 and forward
  * @return {Promise} returns Promise if no callback passed
  */
 Db.prototype.eval = function(code, parameters, options, callback) {