Use <command> tag for some more commands. Most already had this.

Use <command> tag for some more commands. Most already had this.
So be consistent.
Add formatting for a configuration option.
Add formatting for a filename.
Uppercase "DNSSEC" in a couple places.
syslog "logs" (not "prints").
Also add formatting for some command line options. (NOTE: this is not
consistent yet, as some use <command> and some use <option> -- need
to define this in a style guide.)

(Note this was committed for v9_4. Two changes were not brought down
from HEAD, because corresponding sentences didn't even exist here.
I don't plan on investigating that further.)