Improved clipboard API

Change the internal clipboard API to use a request based model in
order to be prepared for more advanced clipboard transfers.
diff --git a/vncviewer/CConn.cxx b/vncviewer/CConn.cxx
index 2cc1fe4..6ba3276 100644
--- a/vncviewer/CConn.cxx
+++ b/vncviewer/CConn.cxx
@@ -377,11 +377,6 @@
   fl_beep();
 }
 
-void CConn::serverCutText(const char* str)
-{
-  desktop->serverCutText(str);
-}
-
 void CConn::dataRect(const Rect& r, int encoding)
 {
   sock->inStream().startTiming();
@@ -422,6 +417,21 @@
   desktop->setLEDState(state);
 }
 
+void CConn::handleClipboardRequest()
+{
+  desktop->handleClipboardRequest();
+}
+
+void CConn::handleClipboardAnnounce(bool available)
+{
+  desktop->handleClipboardAnnounce(available);
+}
+
+void CConn::handleClipboardData(const char* data)
+{
+  desktop->handleClipboardData(data);
+}
+
 
 ////////////////////// Internal methods //////////////////////