feature.pl: stop using "switch" as a demo feature!

It is experimental, it would cause warnings, and frankly, I would
like to just inch toward its disappearance.

lib/feature.pm

@@ -85,16 +85,15 @@ feature - Perl pragma to enable new features
 
 =head1 SYNOPSIS
 
-    use feature qw(say switch);
-    given ($foo) {
-        when (1)          { say "\$foo == 1" }
-        when ([2,3])      { say "\$foo == 2 || \$foo == 3" }
-        when (/^a[bc]d$/) { say "\$foo eq 'abd' || \$foo eq 'acd'" }
-        when ($_ > 100)   { say "\$foo > 100" }
-        default           { say "None of the above" }
-    }
+    use feature qw(fc say);
+
+    # Without the "use feature" above, this code would not be able to find the
+    # built-ins "say" or "fc":
+    say "The case-folded version of $x is: " . fc $x;
+
 
-    use feature ':5.10'; # loads all features available in perl 5.10
+    use feature ':5.10';  # sets features to match the :5.10 bundle, which
+                          # may turn off or on multiple features (see below)
 
     use v5.10;           # implicitly loads :5.10 feature bundle
 

regen/feature.pl

@@ -491,16 +491,15 @@ =head1 NAME
 
 =head1 SYNOPSIS
 
-    use feature qw(say switch);
-    given ($foo) {
-        when (1)          { say "\$foo == 1" }
-        when ([2,3])      { say "\$foo == 2 || \$foo == 3" }
-        when (/^a[bc]d$/) { say "\$foo eq 'abd' || \$foo eq 'acd'" }
-        when ($_ > 100)   { say "\$foo > 100" }
-        default           { say "None of the above" }
-    }
+    use feature qw(fc say);
+
+    # Without the "use feature" above, this code would not be able to find the
+    # built-ins "say" or "fc":
+    say "The case-folded version of $x is: " . fc $x;
+
 
-    use feature ':5.10'; # loads all features available in perl 5.10
+    use feature ':5.10';  # sets features to match the :5.10 bundle, which
+                          # may turn off or on multiple features (see below)
 
     use v5.10;           # implicitly loads :5.10 feature bundle