- typos

- typos
- Add double spaces following full stops to improve typeset output
- mdoc-ification.  (Though I'm uncertain whether option values and
  contents should be .Dq or something else).
- Fix a missed /etc/ssh change
- Expand wording on RandomSeed and behaviour when X11 isn't forwarded.
- Change examples to literal mode.
- Trim trailing whitespace

PR:		docs/17292
Submitted by:	Peter Jeremy <peter.jeremy@alcatel.com.au>