incompatible Kawa changes

[Per Bothner <per at bothner dot com>]

As threatened I've checked in some major incompatible changes:

- A Scheme string literal is now a java.lang.String instance.
- In general Scheme strings implement java.lang.CharSequence.
- Note that CharSequence does not exist in JDK 1.3.  I've tried to
get this to work so that if you (say) configure --with-java-source=2
then it should still work, but I don't have any easy way to test this.
- A Scheme symbol is now a gnu.mapping.SimpleSymbol, which extends
gnu.mapping.Symbol.
- The expression <java.lang.Integer> now evaluates to a Class object
(like Java's java.lang.Integer.class), not a gnu.type.ClassType object.
- A classname like java.lang.Integer also evaluates to Integer.class,
assuming the classname is otherwise lexically bound *and* the class
exists in the classpath at compile time.
- The name bound by define-simple-class is still a ClassType,
but I intend to change that next.

Please try this out on your source code.  If it looks like updating
your source code will be a major undertaking, let me know and we'll
try to see if we can come up with some compatibility mechanism to
reduce the pain.

http://www.gnu.org/software/kawa/news.html
--
	--Per Bothner
per@bothner.com   http://per.bothner.com/