Clear storage

[shiffman]

Add a function to clear local storage, not sure if worth adding a button or just something undocumented you can call from the console if need be.

[shiffman]

Ah, jsut realized there is the p5 clearStorage() function which does the trick, so it's just a matter of deciding if we want an interface element. Maybe before adding more interface elements it would be helpful to improve the current layout as is #4