fix(model): remove limit from findById

lib/model.js

@@ -1432,8 +1432,6 @@ Model.prototype.findById = function(param, options) {
     throw new Error('Argument passed to findById is invalid: '+param);
   }
 
-  options.limit = 1;
-
   // Bypass a possible overloaded findAll.
   return Model.prototype.findAll.call(this, _.defaults(options, {
     plain: true