[development] parameters for diff

[Gerhard Killesreiter]

Peter Wolanin wrote:
> As far as I can tell,  the commands:
> 
> "diff -u -F^f"  and  "diff -u -p"
> 
> produce the same output.  However, the former seems to be preferred in
> the handbook documentation.  Is there some reason to prefer it?

No, there is only a historical reason: When I read the diff docs -F^f 
made more sense to me. -p refers to C which isn't PHP. :p

Cheers,
	Gerhard