Build procedure: generation of .h files

[John Keiser]

        Issue 1: lib must come before native in order for it to depend on Classpath
classes.
        Issue 2: .h files should depend on their respective classes, in case they
change.
        Issue 3: Is there an automagic rule that could do .h files?  Something that
could do *.h: *.class and figure out dependencies using Makefile's regular
expression?
        Issue 4: That rule would have to use Classpath's classpath when it ran
javah.
--John Keiser