Fleishman puzzle (refined, customizable)

This is a remix of the [Fleishman Puzzle by plastic](http://www.thingiverse.com/thing:235952), based on the work of [Gregg Fleishman](http://www.greggfleishman.com/PYRAMID.html).

The only changes are that the OpenSCAD file is [Customizer](https://www.thingiverse.com/apps/customizer/run?thing_id=1830873)-friendly, parameters can be changed independently without affecting other parameters, and the tolerance parameter is now an absolute value. Moreover, it shows the *correct* solution in animati