Added ToDo app for learning.

This is based on a tutorial from ios-blog.co.uk named, “Developing iOS8
Apps Using Swift – Create a To-Do Application”.

http://ios-blog.co.uk/tutorials/developing-ios8-apps-using-swift-create-
a-to-do-application/

The app isn’t written yet, I’ll commit each step along the way. All
I’ve done is set up the first textfield element.