Use the full URL for R libs

This allows the user to download the file and use the interactive table or chart.

webserver/cgi-bin/index.pl

@@ -309,7 +309,7 @@ =head2 validate_form
 
 sub validate_form {
     my $data;
-    my $validated_args = ["--web", ($WEB_ROOT or "/")];
+    my $validated_args = ["--web", $q->url(-base=>1).($WEB_ROOT or "/")];
     my @error_messages;
     
     my $input_data;