PHP Login Pad Class: Display and validate digits for the user to enter

This class can display and validate digits for the user to enter.

It can take code made of digits from 0 to 9 and renders a pad arranged randomly made of 16 buttons that the user needs to click on the right buttons to match the validate code digits.

The class can also check if the user has clicked on the right buttons with digits that match the code that was provided initially.

Depending on the configuration of the class, the code can be typed on the keyboard or necessarily with the mouse. It can optionally be used to avoid robots.