Update index.md with Angular IDE listing (#871)
Update index.md with Angular IDE listing (#871)

Adding a new freemium IDE for TypeScript, ES 6 and Angular development.
ionic-team/ionic-site,driftyco/ionic-site,driftyco/ionic-site,driftyco/ionic-site,driftyco/ionic-site,driftyco/ionic-site,ionic-team/ionic-site,ionic-team/ionic-site,ionic-team/ionic-site