Fix issue #21: DocBook 5 does not even allow following our suggestion
Fix issue #21: DocBook 5 does not even allow following our suggestion

Nesting command and option elements was (barely) allowed in DocBook 4.
In DocBook 5, it is completely forbidden. So, all we did there was annoy
authors.

sknorr/suse-doc-style-checker,sknorr/suse-doc-style-checker,sknorr/suse-doc-style-checker