Remove full support for colour maps

Gets rid of a loooot of code and complexity.

Colour map clients are still supported through an
automatically generated map, but we lose the ability to
develop a client or server that uses colour maps
internally.
diff --git a/unix/x0vncserver/XPixelBuffer.cxx b/unix/x0vncserver/XPixelBuffer.cxx
index aa52620..f88eda4 100644
--- a/unix/x0vncserver/XPixelBuffer.cxx
+++ b/unix/x0vncserver/XPixelBuffer.cxx
@@ -29,7 +29,7 @@
 using namespace rfb;
 
 XPixelBuffer::XPixelBuffer(Display *dpy, ImageFactory &factory,
-                           const Rect &rect, ColourMap* cm)
+                           const Rect &rect)
   : FullFramePixelBuffer(),
     m_poller(0),
     m_dpy(dpy),
@@ -54,7 +54,6 @@
   width_ = rect.width();
   height_ = rect.height();
   data = (rdr::U8 *)m_image->xim->data;
-  colourmap = cm;
 
   // Calculate the distance in pixels between two subsequent scan
   // lines of the framebuffer. This may differ from image width.
diff --git a/unix/x0vncserver/XPixelBuffer.h b/unix/x0vncserver/XPixelBuffer.h
index 29ae94a..ab4f88e 100644
--- a/unix/x0vncserver/XPixelBuffer.h
+++ b/unix/x0vncserver/XPixelBuffer.h
@@ -37,8 +37,7 @@
 class XPixelBuffer : public FullFramePixelBuffer
 {
 public:
-  XPixelBuffer(Display *dpy, ImageFactory &factory,
-               const Rect &rect, ColourMap* cm);
+  XPixelBuffer(Display *dpy, ImageFactory &factory, const Rect &rect);
   virtual ~XPixelBuffer();
 
   // Provide access to the underlying Image object.
diff --git a/unix/x0vncserver/x0vncserver.cxx b/unix/x0vncserver/x0vncserver.cxx
index 165441f..ee39fae 100644
--- a/unix/x0vncserver/x0vncserver.cxx
+++ b/unix/x0vncserver/x0vncserver.cxx
@@ -135,7 +135,7 @@
 };
 
 
-class XDesktop : public SDesktop, public ColourMap, public TXGlobalEventHandler
+class XDesktop : public SDesktop, public TXGlobalEventHandler
 {
 public:
   XDesktop(Display* dpy_, Geometry *geometry_)
@@ -199,7 +199,7 @@
     ImageFactory factory((bool)useShm, (bool)useOverlay);
 
     // Create pixel buffer and provide it to the server object.
-    pb = new XPixelBuffer(dpy, factory, geometry->getRect(), this);
+    pb = new XPixelBuffer(dpy, factory, geometry->getRect());
     vlog.info("Allocated %s", pb->getImage()->classDesc());
 
     server = (VNCServerST *)vs;
@@ -269,20 +269,6 @@
     return Point(pb->width(), pb->height());
   }
 
-  // -=- ColourMap callbacks
-  virtual void lookup(int index, int* r, int* g, int* b) {
-    XColor xc;
-    xc.pixel = index;
-    if (index < DisplayCells(dpy,DefaultScreen(dpy))) {
-      XQueryColor(dpy, DefaultColormap(dpy,DefaultScreen(dpy)), &xc);
-    } else {
-      xc.red = xc.green = xc.blue = 0;
-    }
-    *r = xc.red;
-    *g = xc.green;
-    *b = xc.blue;
-  }
-
   // -=- TXGlobalEventHandler interface
 
   virtual bool handleGlobalEvent(XEvent* ev) {