Functional expansion LCD 12864 display menu system

[DIY-O-Sphere]

Making a change in the 12864 display menu system to behave an image like a button.
Clicking the image should execute an action.

@dc42
As discussed here
https://forum.duet3d.com/topic/13660/display-filename-on-12864/6?_=1578509633300
Maybe here is the better place to remember...