updated dist

Author: janschoenherr

dist/vue-form.js

@@ -140,6 +140,10 @@ return /******/ (function(modules) { // webpackBootstrap
 	    _.isString = function (value) {
 	        return typeof value === 'string';
 	    };
+	    
+	    _.isUndefined = function (value) {
+	        return typeof value === 'undefined';
+	    };
 
 	    return _;
 	};