cd path searching

[arnold@infographix.infographix.com (Arnold Robbins)]

This perhaps should go in private mail to Paul. On the other hand, maybe
everyone else agrees with me ... (if not, I'm sure I'll find out in a hurry!)

Anyway, I noticed that in es-0.90 alpha, the cdpath searching code was
removed from init.es.  This is one thing that I use day in, day out,
and rely on extremely heavily. It is, in fact, what has kept me from
switching to the new version from 0.84.  Much as I hate to have to
admit this, I really am too busy (or lazy :-) to bother ripping the
code out of the old version and putting it in my .esrc.

So, can we please put it back into init.es?  Maybe inside an if for a
variable or something so that people can turn it off if they don't want it,
or even turn it on if they do.

Thanks,

Arnold Robbins