QUNIT2 upgrade

This updates the tests to use QUnit@2.x.x.

#22

IE11 Support

#19

Fixes issue with enumerability of added functions

v2.1.0

2.1.0

v1.1.0

• Add "use strict" #13

API is now a mixin-based

import DefineMap from "can-define/map/map";
import defineBackup from "can-define-backup";

const recipe = new DefineMap( "Recipe", {
    title: "Pancake Mix"
} );
defineBackup(recipe);

#12