DEV: select-kit 2 (#7998)

This new iteration of select-kit focuses on following best principales and disallowing mutations inside select-kit components. A best effort has been made to avoid breaking changes, however if you content was a flat array, eg: ["foo", "bar"] You will need to set valueProperty=null and nameProperty=null on the component.

Also almost every component should have an `onChange` handler now to decide what to do with the updated data. **select-kit will not mutate your data by itself anymore**

test/javascripts/components/select-kit/select-kit-test-helper.js.es6

@@ -0,0 +1,33 @@
+import selectKit from "helpers/select-kit-helper";
+
+export function testSelectKitModule(moduleName, options = {}) {
+  moduleForComponent(`select-kit/${moduleName}`, {
+    integration: true,
+    beforeEach() {
+      this.set("subject", selectKit());
+      options.beforeEach && options.beforeEach.call(this);
+    },
+    afterEach() {
+      options.afterEach && options.afterEach.call(this);
+    }
+  });
+}
+
+export const DEFAULT_CONTENT = [
+  { id: 1, name: "foo" },
+  { id: 2, name: "bar" },
+  { id: 3, name: "baz" }
+];
+
+export function setDefaultState(ctx, value, options = {}) {
+  const properties = Object.assign(
+    {
+      onChange: v => {
+        this.set("value", v);
+      }
+    },
+    options || {}
+  );
+
+  ctx.setProperties(properties);
+}