gitweb: 'pickaxe' and 'grep' features requires 'search' to be enabled

Both 'pickaxe' (searching changes) and 'grep' (searching files)
require basic 'search' feature to be enabled to work.  Enabling
e.g. only 'pickaxe' won't work.

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Signed-off-by: Jakub Narebski <jnareb@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

gitweb/gitweb.perl

@@ -320,6 +320,7 @@ our %feature = (
 	# Enable grep search, which will list the files in currently selected
 	# tree containing the given string. Enabled by default. This can be
 	# potentially CPU-intensive, of course.
+	# Note that you need to have 'search' feature enabled too.
 
 	# To enable system wide have in $GITWEB_CONFIG
 	# $feature{'grep'}{'default'} = [1];
@@ -334,6 +335,7 @@ our %feature = (
 	# Enable the pickaxe search, which will list the commits that modified
 	# a given string in a file. This can be practical and quite faster
 	# alternative to 'blame', but still potentially CPU-intensive.
+	# Note that you need to have 'search' feature enabled too.
 
 	# To enable system wide have in $GITWEB_CONFIG
 	# $feature{'pickaxe'}{'default'} = [1];