Add new scene controller with touch display example.

Upgraded RF24 to latest version which supports SoftSPI. 
Added DigitalIO and UTFT libraries to support the new example.
Fix problem reported in RelayWithButtonActuator example.

libraries/UIPEthernet/utility/clock-arch.c

@@ -0,0 +1,28 @@
+/*
+ clock-arch.c - Arduino implementation of uIP clock device.
+ Copyright (c) 2010 Adam Nielsen <malvineous@shikadi.net>
+ All rights reserved.
+
+ This library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ This library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with this library; if not, write to the Free Software
+ Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+#include <Arduino.h>
+#include "clock-arch.h"
+
+clock_time_t
+clock_time(void)
+{
+  return (clock_time_t) millis();
+}