[racket] plist limitations

At Wed, 4 Apr 2012 16:06:54 -0600, Matias Eyzaguirre wrote:
> The plist library in xml/plist will only allow for plists whose root
> element is a dictionary, and complains bitterly when it is anything
> else. However many plists have an array in their root. I'm unsure
> what the reasoning for this is, but I think it could be considered a
> bug

Generalizing `read-plist' and `write-plist' makes sense to me --- and
it seems consistent with functions in CoreFoundation --- so I've pushed
the change.