fix for CLASSPATH/classpath switch behaviour

[Tom Tromey]

>>>>> "Nic" == Nic Ferrier <nferrier@tapsellferrier.co.uk> writes:

Nic> Unfortunately, this does not match what Sun's javac compiler
Nic> does. With javac the -classpath switch does NOT override the
Nic> system class path.

Does the Sun javac have a way to override the system class path?
What is it?

Nic> The attached patch solves the problem. It simply swaps the
Nic> meaning of the two options.

I'd like to see this patch refined in three ways:

* It leaves jcf-path.c alone, meaning that the function names and
  comments therein will be confusing, and

* It doesn't update the docs, and

* lang-options.h has to change

Tom