Fix some text and format string.
Alternative usage of admins - them be the pingers.

- Provide a method so that only admins can do the pinging.
Allow JIDs to be used to determine admins

- This allows the use of static configuration for admin JIDs, including
  and up to resource limitation or just simply user names.
Oh have to escape user supplied strings...

 - Formats strings can be hard.
Rounding out test coverage.