Add basic eq helper

We could also consider using https://github.com/jmurphyau/ember-truth-helpers instead if we start to use this more and/or need other, related helpers

Author: Turbo87

app/helpers/eq.js

@@ -0,0 +1,7 @@
+import { helper } from '@ember/component/helper';
+
+export function eq([a, b]) {
+  return a === b;
+}
+
+export default helper(eq);