Fixed hiding bugs

in case-lambda, fixed renaming bug
  in let-values and letrec-values, fixed hiding on errors
  fixed do-rename loop; now let bound-id=? works as expected!
Added hide.ss to debug.ss exports

svn: r4347

original commit: 27ce8d0f3b6725bad6eb14eb2726847a838d21f5

collects/macro-debugger/model/debug.ss

@@ -3,6 +3,7 @@
   (require (lib "plt-match.ss"))
   (require "trace.ss"
            "deriv-util.ss"
+           "hide.ss"
            "hiding-policies.ss"
            "deriv.ss")
 
@@ -10,6 +11,7 @@
            (all-from "deriv.ss")
            (all-from "deriv-util.ss")
            (all-from "hiding-policies.ss")
+           (all-from "hide.ss")
            (all-from (lib "plt-match.ss"))
            find-deriv)