fix the resolver mess, and add glut to the build

fix the resolver mess, and add glut to the build

* maint/update-low-level-bindings (write-scm): Update to use
  module-specific runtimes, and to generate define-FOO-procedure forms.
  This way modules can control how their symbols are loaded.

* figl/runtime.scm: Remove the default resolver; instead have
  define-foreign-procedure take a resolver form.

* figl/gl/runtime.scm:
* figl/glu/runtime.scm:
* figl/glut/runtime.scm:
* figl/glx/runtime.scm: New support modules.

* figl/gl/low-level.scm:
* figl/glu/low-level.scm:
* figl/glx/low-level.scm: Regenerate.

* figl/glut/low-level.scm: Change to use define-glut-procedure, and to
  delegate all the resolver business to the runtime module.

* Makefile.am: Add new files, and add glut to the build.