houston, we have hygiene

houston, we have hygiene

* module/ice-9/expand-support.scm (strip-expansion-structures): Enable
  @/@@ substitution.

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

* module/ice-9/psyntax.scm: Since syntax objects are quotable, make the
  module field the module name, not the module itself. Scope the operand
  of global calls appropriately. Thread modules through syntax-dispatch
  destructuring. Houston, we have hygiene.

* module/ice-9/syncase.scm: Adapt to module / module-name changes.