Create a configuration option for non-square grid

[gheja]

I've noticed while working with Tamil letters for Issue #203 and when checking some forks that the square grid could not fit all (non-english) letters.

I think there should be a configuration option to change the aspect ratio (and font size?) of the grid to fit those letters.

I'd not go with autodetection as that can be tricky and changing the grid during play would look awkward IMHO. It's better if the owner of the fork decided what to fit.

@muhelen provided a screenshot with actual words in the Unicode support thread: