Move SUSv2 obsolete feature disabling to debug menu, invert meaning of

symbol (switched on to remove now: test your apps to make sure they _don't_
do this, because as some point we should just yank it), fixup head/tail/fold.

Also tweak "make allyesconfig" so anything starting with CONFIG_DEBUG gets
left switched off.  Possibly other things we want to put in the debug menu?

Config.in

@@ -251,23 +251,6 @@ config CONFIG_BUILD_AT_ONCE
 
 	  Say 'N' unless you know what you are doing.
 
-config CONFIG_FEATURE_SUSv2
-	bool "Enable features that are in SuSv2 but not SuSv3?"
-	default y
-	help
-	  This option will enable backwards compatability with SuSv2,
-	  specifically, numeric options such as 'head -1 <file>' will be
-	  supported.
-
-config CONFIG_FEATURE_SUSv2_OBSOLETE
-	bool "Enable features that are obsolete in SuSv2"
-	depends on CONFIG_FEATURE_SUSv2
-	default y
-	help
-	  Enable pre- SuSv2 features which are deprecated in SuSv2 and
-	  above.
-	  Disables support for e.g. numeric arguments in fold.
-
 endmenu
 
 menu 'Installation Options'
@@ -389,5 +372,13 @@ config CONFIG_EFENCE
 
 endchoice
 
+config CONFIG_DEBUG_YANK_SUSv2
+	bool "Disable obsolete features removed before SUSv3?"
+	default y
+	help
+	  This option will disable backwards compatability with SuSv2,
+	  specifically, old-style numeric options ('command -1 <file>')
+	  will not be supported in head, tail, and fold.  (Note: should
+	  yank from renice too.)
 
 endmenu