NumDirectoryGuards now tracks NumEntryGuards by default

Now a user who changes only NumEntryGuards will get the behavior she
expects. Fixes bug 9354; bugfix on 0.2.4.8-alpha.
Fix invalid-read when a managed proxy configuration fails.
Merge remote-tracking branch 'arma/bug9354' into maint-0.2.4
Merge branch 'maint-0.2.4' into release-0.2.4