Provide a local Object.assign polyfill if browser doesn't have it

[termi]

For classes:

class A {}

class B inherit A {}

->

var assing$N = Object.assign||function(t,s){for(var p in s)if (s.hasOwnProperty(p)){t[p]=s[p]};return t};
var A = (function(){
    function A() {   }
return A;})();
var B = (function(_super){assing$N.call(Object, B, A);
    function B() {   }
return A;})(A);