Usability improvements

[Hermanya]

Hello! I think it would be great to have a handy way to tune basic things like:

• font family,
• font size and
• the color theme.

It could be implemented as a neat pop-over, inspired by apple's iBooks.

If you like the idea, I can make it happen.

[nijikokun]

I agree, it's something I was intending to add to my theme

[AaronO]

👍 I like the idea.

It would be great if you are willing to do a PR with this, and keep a consistent look and feel with @nijikokun's clarity theme (gitbook's default).

Also don't forget to persist the user's settings in localStorage ;)

[Hermanya]

Alright then.