(FACT-646) Cherry-pick updated debian control file back into master

This commit cherry-picks work done on Facter's Debian/control file
back into master, which was lost during the facter-2 / master merge.

debian/control: Recommend lsb-release.

Recommending lsb-release should be enough to have it pulled in by
default on most Debian distributions solving the issue where the lsb*
facts and those depending on them weren't working.