removing Find_Unused_Assms_Examples from session as it requires much time

--- a/src/HOL/Quickcheck_Examples/Find_Unused_Assms_Examples.thy	Sun Feb 26 21:44:12 2012 +0100
+++ b/src/HOL/Quickcheck_Examples/Find_Unused_Assms_Examples.thy	Mon Feb 27 10:56:36 2012 +0100
@@ -25,4 +25,4 @@
 find_unused_assms List
 find_unused_assms Map
 
-end
\ No newline at end of file
+end

--- a/src/HOL/Quickcheck_Examples/ROOT.ML	Sun Feb 26 21:44:12 2012 +0100
+++ b/src/HOL/Quickcheck_Examples/ROOT.ML	Mon Feb 27 10:56:36 2012 +0100
@@ -1,5 +1,4 @@
 use_thys [
-  "Find_Unused_Assms_Examples",
   "Quickcheck_Examples",
   "Quickcheck_Lattice_Examples"
 ];