bytecode2 branch of Kawa uses ASM

[Per Bothner]

Tom Bousso for a Google Summer of Code project ported the gnu.bytecode
code-generation library to sit on top of the ASM package. This has the
advantage of making use of the gnu.bytecode high-level operations (including
better consistency checking) while using the popular (and more actively developed)
ASM library for lower-level class-file generation.

A version of Kawa using ASM and the re-written gnu.bytecode is in the
'bytecode2' branch of the Kawa git repository:
https://gitlab.com/kashell/Kawa/tree/bytecode2

Today I merged in the most recent Kawa 3.0 changes from master.

On the whole this branch works pretty well. There are some testsuite failures
because the tests depend on features in the asm-all.jar rather then the
smaller asm.jar, and I haven't decided how to handle this. There also
appears to be an infinite loop in the XQTS tests in gnu/xquery/testsuite
(which are not enabled by default).

So there is still some work to do, but I expect to merge this branch
into master at some point before the next major Kawa release.

Thanks to Tom - and Google for sponsoring him.