1.0.21.9: refactor toplevel option processing somewhat

1.0.21.9: refactor toplevel option processing somewhat

 * --disable-debuger takes effect before init files are processed.

 * Don't resignal errors in annotated form: this loses restarts originally
   established with (RESTART-CASE (ERROR ...) ...).

 * Make the restarts we provide more explicit about the cause of the
   error, including the exact commandline option (or initialization
   file name and kind) in the restart text.

 * Mark (THROW NO-SUCH-TAG) in debug.impure.lisp as expected to fail
   on x86/Darwin -- though this patch is obviously unrelated,
   something jiggers things just enough for the backtrace to go
   astray.

 * Based on patch by Ariel Badichi.