Mention new setup script in "no config" mode.

I was also half-tempted to just force-exec the setup script if it's
available and there's no config, but there are some scenarios where it
might make sense to just download kdesrc-build and kick off a very quick
build from there (especially with the +xml-module syntax on the command
line).

kdesrc-build

@@ -1208,17 +1208,16 @@ EOM
         my $homepage = "http://kdesrc-build.kde.org/";
 
         note (<<"HOME");
-    Unable to open configuration file!
-    We looked for:
-        $searched
+Unable to open configuration file!
+We looked for:
+    $searched
 
-    kdesrc-build will continue using a default set of options.  These options may
-    not apply to you, so feel free to visit the kdesrc-build homepage
+You should create a configuration file. The file kdesrc-buildrc-sample should
+be included with your kdesrc-build package, which you can copy to
+~/.kdesrc-buildrc and edit from there.
 
-    b[g[$homepage]
-
-    and access the kdesrc-build documentation.  Also the latest release package
-    will have a sample configuration file that you can edit to your liking.
+If the b[kdesrc-build-setup] program is installed, you can run that program
+to quickly generate a simple configuration to get started.
 HOME
     }