Revert "README.md: add docbook-xsl to the recommended debian packages for building the documentation"
Revert "README.md: add docbook-xsl to the recommended debian packages for building the documentation"

This reverts commit 78c2eeedd029d66fa506bb2ad2483e7b70bd9f96.

hstern/nmsg,hstern/nmsg,hstern/nmsg,hstern/nmsg,hstern/nmsg