Change status return code to RC_OK (200)

Status 204 (RC_NO_CONTENT) is actually the correct one, since we are not
retuning any content, but apparently gitlab is (no longer?) smart enough
to recoginze all 2xx codes as being okay, and seens to want to see 200

tools/git/gitmaild

@@ -172,9 +172,9 @@ while (my $connection = $listen_socket->accept()) {
                 # This means it worked, but we are not going to return any
                 # content to the caller
                 if ($verbose) { 
-                    print "Returing status code " . RC_NO_CONTENT .  "\n";
+                    print "Returing status code " . RC_OK .  "\n";
                 }
-                $connection->send_status_line(RC_NO_CONTENT);
+                $connection->send_status_line(RC_OK);
                 $connection->close();
                 exit 0;
             }