Add mono select input

[GMartigny]

Add mono-select input. Should work like <select> or <input type="radio">, but could be better designed.

Solution	Pros	Cons
Drop-down	Compact	Should handle overflow/scroll and complex
Radial	Smart and fun	Limited number of items
Radio	Display every options	How to group them ?

[GMartigny]

Drop-down version added by 2312a8f.

[GMartigny]

Radial rotating input added by ed95cb4