[Asterisk-doc] More updates to CLI application reference

[Jared Smith]

I've started making some formatting changes to Appendix 3, to make the
formatting a little fancier.  If someone's got some time over then next
24 hours, would they mind doing more work on it?  If not, I'll finish it
when I get more free time.

(If you don't like the way I've formatted it, let me know.  I'm assuming
the lack of complaints means I must be doing something right!)

Jared