refactor: MAJOR

- modernize code to ES6 syntax
- async/await interface
- switch to ava for testing
- update tests

Author: kessler

.gitignore

@@ -26,4 +26,7 @@ node_modules
 
 # see https://github.com/substack/browserify-handbook#organizing-modules
 node_modules/*
-!node_modules/app
+!node_modules/app
+
+index2.js
+test2.js