Change to README ought to be reverted

[Patrick R. Michaud]

On Tue, Jul 26, 2011 at 10:35:19PM -0700, Christoph Otto wrote:
> I strongly agree with the sentiment here.  If an optimized Parrot is
> broken on a platform, we need to fix that bug.  

For whatever it's worth, https://gist.github.com/1109203
shows the difference in timings between an optimized and
non-optimized parrot.  In general, on my machines running
Parrot without --optimize causes programs to take twice as
long.

Both Rakudo and NQP are hardwired to pass "--optimize" to
Parrot's configuration when building Parrot with 
"--gen-parrot" , because Parrot's default (no --optimize)
really makes sense only for Parrot developers and not
Parrot users.

Pm