PATCH: Add more documentation for prerequisites

[Daniel Jacobowitz]

On Wed, Jul 20, 2005 at 07:39:14AM -0700, Mark Mitchell wrote:
> Prerequisites seem to confuse a lot of people; here's a documentation 
> update that tries to clarify their purpose and the fact that you should 
> not use prerequisite tests to try to make one test depend on 
> side-effects from another test.

Thanks - this is much clearer.

-- 
Daniel Jacobowitz
CodeSourcery, LLC