more work towards compiling and interpreting keyword args

* libguile/_scm.h (SCM_OBJCODE_MINOR_VERSION): Bumparoo
* libguile/vm-i-system.c (push-rest, bind-rest): Logically there are
  actually two rest binders -- one that pops, conses, and pushes, and
  one that pops, conses, and local-sets. The latter is used on keyword
  arguments, because the keyword arguments themselves have been shuffled
  up on the stack. Renumber ops again.

* module/language/tree-il/compile-glil.scm (flatten): Attempt to handle
  compilation of lambda-case with keyword arguments. Might need some
  help.

* module/ice-9/psyntax.scm (build-lambda-case): An attempt to handle the
  interpreted case correctly. This might need a couple iterations, but
  at least it looks like the compile-glil code.

* module/ice-9/psyntax-pp.scm: Regenerated.

* module/language/glil.scm (<glil>): Rename "rest?" to "rest" in
  <glil-opt-prelude> and <glil-kw-prelude>, as it is no longer a simple
  boolean, but if true is an integer: the index of the local variable to
  which the rest should be bound.

* module/language/glil/compile-assembly.scm (glil->assembly): Adapt to
  "rest" vs "rest?". In the keyword case, use "bind-rest" instead of
  "push-rest".

* test-suite/tests/tree-il.test: Update for opt-prelude change.

libguile/_scm.h

@@ -172,7 +172,7 @@
 
 /* Major and minor versions must be single characters. */
 #define SCM_OBJCODE_MAJOR_VERSION 0
-#define SCM_OBJCODE_MINOR_VERSION I
+#define SCM_OBJCODE_MINOR_VERSION J
 #define SCM_OBJCODE_MAJOR_VERSION_STRING        \
   SCM_CPP_STRINGIFY(SCM_OBJCODE_MAJOR_VERSION)
 #define SCM_OBJCODE_MINOR_VERSION_STRING        \