Added: In blocks, [[foo]] is mapped to \label{foo}.
       If there is no element [[...]], then an automatic
       label, modestly informative, is generated.  There
       is a question of whether in this latter case we
       should simply do nothing.
Merge branch 'master' of https://github.com/jxxcarlson/asciidoctor-backends

Conflicts:
	ruby/latex/run