Changeset of plot.m (was Set impulses plot style works incorrectly)

[John W. Eaton]

On  5-Sep-2008, Tatsuro MATSUOKA wrote:

| Hello 
| 
| The doument of plot.m had a mistakes concerning symbol mark '^'.
| At octave 2.1.xx, it indicates  'Set impulses plot style'.
| However '^' indiates plot point sytel is triangle.
| 
| So I proposed the below patch to plot.m 

I applied it.

Thanks,

jwe