tidy up SECURITY:HOST_BASED, USER_BASED meta-knobs based on ZKM's input #4031
===VersionHistory:None===
added placeholders for 2 items that we will want to elaborate on for the
8.2.0 release. This isn't part of the 8.1.6 released manual, but is
necessary and must not be forgotten
Merge branch 'V8_1_6-branch' of /p/condor/repository/CONDOR_SRC into V8_1_6-branch
Merge branch 'V8_1_6-branch'