KNL-1184 minor fixes and improvements to the names of config items, forced disk to always off

git-svn-id: https://source.sakaiproject.org/svn/config/trunk@308161 66ffb92e-73f9-0310-93c1-f5514f145a0a
KNL-1184 fixing up the config docs

git-svn-id: https://source.sakaiproject.org/svn/config/trunk@308167 66ffb92e-73f9-0310-93c1-f5514f145a0a