build-matrix: Split huge command into smaller ones

Just outputting each line on its own doesn't impact performance that
much (7s to 7.5s on my system).

On my system: 3.5s -> 4.5s, which is not to bad. --TG

Signed-off-by: Timothy Gu <timothygu99@gmail.com>
css: Make row headers left-aligned

Signed-off-by: Timothy Gu <timothygu99@gmail.com>
Add package versions to build-matrix.

This is a bit ugly at the moment, since there are some pretty long
version numbers in MXE...
build-matrix: make each tag a new line

Dunno how to fix the indentation, but this already looks way better
than before.

Signed-off-by: Timothy Gu <timothygu99@gmail.com>
Merge branch 'build-matrix-work'

Merges #526.