Progress bars instead of numbers in grid

[Torgen]

If we don't usually care about going to the puzzles via the links in the grid and instead only care about it as an indicator of progress, we could replace the numbered links with a progress bar.
http://getbootstrap.com/2.3.2/components.html#progress
We would probably want to group the solved puzzles together, then the stuck puzzles, then the rest. We could also support an "expected size" tag for when we know how big a meta will be, but we haven't unlocked all the puzzles in it, so we can represent them with blank space.
Mutually exclusive with #348 unless a switch is provided for it.