Backport the LaTeX style fixes from zubaxdoc.cls

This is what the spec should be formatted like when built correctly:

This is what I'm getting after downloading build artifacts from GitLab:

Section headers are offset from the left for some reason, which breaks alignment and makes the doc look sloppy. I think it's important that we get consistent results on local machines and from the CI, otherwise, we might accidentally publish a bad doc.

My environment is Linux Mint 18 Sarah with texlive-full and lyx.

I seem to have the latest version available in the Ubuntu repos:

$ apt-cache policy texlive-full
texlive-full:
  Installed: 2015.20160320-1ubuntu0.1
  Candidate: 2015.20160320-1ubuntu0.1
  Version table:
 *** 2015.20160320-1ubuntu0.1 500
        500 http://archive.ubuntu.com/ubuntu xenial-updates/universe amd64 Packages
        500 http://archive.ubuntu.com/ubuntu xenial-updates/universe i386 Packages
        500 http://security.ubuntu.com/ubuntu xenial-security/universe amd64 Packages
        500 http://security.ubuntu.com/ubuntu xenial-security/universe i386 Packages
        100 /var/lib/dpkg/status
     2015.20160320-1 500
        500 http://archive.ubuntu.com/ubuntu xenial/universe amd64 Packages
        500 http://archive.ubuntu.com/ubuntu xenial/universe i386 Packages

Another problem:

@kjetilkjeka seems like the CI is using a newer version of texlive. Perhaps we should just downgrade it to the version specified above, as a temporary solution?

If there is anyone experienced with LaTeX, we could use a hand.