[manual] update for general documentation for random generators

[John W. Eaton]

On 23-Sep-2008, Brian Gough wrote:

| Here is a patch to update the notes about random generators in
| matrix.txi so that the new-style "state" seeding is the primary
| description, and the old-style "seed" part is secondary.
| 
| It also deletes the part about the new random generators all using a
| common state, since that changed earlier this year.
| 
| I wasn't sure which of the old-style generators were truly independent
| in older versions of Octave.  I've written that only rand() and
| randn() are independent, which may need to be corrected.

I applied this patch.

Are you using Mercurial?  If so, could you please submit future
patches by committing to your local archive and then exporting the
change with "hg export".  That makes it easier for me to apply the
changes and give you credit for them.

Thanks,

jwe