[DOC]: Use of horizontal space in Jekyll docs

For a long time I was not sure what exactly I did dislike about the new documentation. I think the main problem is it's inefficient use of horizontal space.

E.g. looking at the [page about transformed reductions in the old documentation](https://thrust.github.io/doc/group__transformed__reductions.html) I can see all of them with one look nicely below each other, using the full width of my screen. Looking at the [newer page](https://nvidia.github.io/thrust/api/groups/group__transformed__reductions.html) I can only see a subset of the algorithms without scrolling. This makes it much harder to get an overview and compare signatures. At the same time almost half of my screen is just the grey background.

Could this be tweaked?