Digital clock behind the text

[RomanSedykh]

Clock like in Alreader for windows. This is very cool feature: you do not wasting screen space for that clock at all, and it is surprisingly easy to get used to.
It must be slightly brighter with a dark background, and slightly darker on bright one. Ability to set custom color for it in options will be nice.

Example:

I must add that in alreader that clock redraws only when you flip the page. It does not change and does not distract you when reading.

[johnfactotum]

The git master version has a footer, and can now be set to display a clock:

The clock changes only when you flip the page.