[cvsnt] Documentation updates

[Tony Hoyle]

I'm currently in the process of updating the documentation, so if anyone 
has anything that is missing/wrong (I know of a few things but probably 
not all) then I'd like to know so I can try to put in.

I'm thinking mostly of undocumented options, commands, etc.  - time 
constraints won't allow for a major rewrite (although if someone really 
wants to do that they're welcome!).

Tony