change count to countDocuments

Author: gendigbadig

lib/mongodb.js

@@ -1322,7 +1322,7 @@ MongoDB.prototype.count = function count(model, where, options, callback) {
     debug('count', model, where);
   }
   where = self.buildWhere(model, where);
-  this.execute(model, 'count', where, function(err, count) {
+  this.execute(model, 'countDocuments', where, function(err, count) {
     if (self.debug) {
       debug('count.callback', model, err, count);
     }