Tardate 2016

This is an extension if the ideas in #196, demonstrating how it's possible to build a "bucket-brigade" of CD4026 chips to drive an arbitrary number of 7-segment LEDs with a single data line.

It just requires the carry-out from the first CD4026 to be chained as the clock input for the second and so on.

As always, all notes, schematics and code are in the Little Arduino Projects repo on GitHub.