Fix error message quotations in install_kdc.rst

Some error messages that kprop could print were quoted incorrectly in
install_kdc.rst.

Also fix minor typos.

(cherry picked from commit 68d7fcf11553c29a2e0c28a57896fbce4a3ef611)

ticket: 7798 (new)
version_fixed: 1.11.5
status: resolved
Better keysalt docs

Add a new section to kdc_conf.rst to describe keysalt lists, and
update other documentation to better distinguish enctype lists from
keysalt lists.

(cherry picked from commit 23a75649277afc24a9dfea199689e18129fa390c)

ticket: 7799 (new)
version_fixed: 1.11.5
status: resolved