Add variable for number of classindex columns

[r0ckarong]

When you are using the default font sizings and have long class names, there can be some overlap of the names in the class index because the columns are too tightly spaced. Allow customizing the number of columns displayed.

[jothepro]

That's a nice idea! It has one problem though: The column size is 3 only on a large screen, but decreases on smaller screens. Your change would override this responsive behaviour. One possible solution could be to restrict the variable to only affect large screens? Or you could define 2 variables, one for medium (>=1120px) & one for large (>=1320px) screens?

[r0ckarong]

That's a nice idea! It has one problem though: The column size is 3 only on a large screen, but decreases on smaller screens.

One possible solution could be to restrict the variable to only affect large screens? Or you could define 2 variables, one for medium (>=1120px) & one for large (>=1320px) screens?

I didn't realize this would scale automatically. I think this can be left as is then. I've reduced the font sizings in my theme anyway so it fits well in all screens regardless.