add assembly intermediate language

add assembly intermediate language

* configure.in:
* module/language/Makefile.am:
* module/language/assembly/Makefile.am: Automakery.

* module/language/assembly.scm:
* module/language/assembly/spec.scm: Add a new language, which is oddly
  even lower than GLIL. I got tired of GLIL's terrible
  compile-objcode.scm, and wanted a cleaner intermediate format.

* module/language/glil/compile-assembly.scm: A purely-functional
  assembler, that produces "assembly". Will document later.

* module/language/glil/spec.scm: Declare the compiler to assembly.