Compile SERVER_ONLY (by #ifdef'ing out all graphics related code).

Does not link yet!!

src/graphics/shared_gpu_objects.cpp

@@ -15,6 +15,8 @@
 //  along with this program; if not, write to the Free Software
 //  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 
+#ifndef SERVER_ONLY
+
 #include "graphics/shared_gpu_objects.hpp"
 #include "graphics/central_settings.hpp"
 
@@ -213,3 +215,6 @@ void SharedGPUObjects::reset()
 {
     m_has_been_initialised = false;
 }   // reset
+
+#endif   // !SERVER_ONLY
+