Added osgSim library which encapulsulates light points.

Added osglightpoint demo.

include/osgSim/Version

@@ -0,0 +1,41 @@
+//C++ header - Open Scene Graph Simulation - Copyright (C) 1998-2002 Robert Osfield
+// Distributed under the terms of the GNU General Public License (GPL)
+// as published by the Free Software Foundation.
+//
+// All software using osgSim must be GPL'd or excempted via the 
+// purchase of the Open Scene Graph Professional License (OSGPL)
+// for further information contact robert@openscenegraph.com.
+
+#ifndef OSGSIM_VERSION
+#define OSGSIM_VERSION 1
+
+#include <osgSim/Export>
+
+extern "C" {
+
+/**
+ * osgSimGetVersion() returns the library version number.
+ * Numbering convention : OpenSceneGraph-Sim-0.1 will return 0.1 from osgSimgetVersion.
+ *
+ * This C function can be also used to check for the existence of the OpenSceneGraph
+ * library using autoconf and its m4 macro AC_CHECK_LIB.
+ *
+ * Here is the code to add to your configure.in:
+ \verbatim
+ #
+ # Check for the OpenSceneGraph-Sim library
+ #
+ AC_CHECK_LIB(osg, osgSimGetVersion, ,
+    [AC_MSG_ERROR(OpenSceneGraph library not found. See http://www.openscenegraph.org)],)
+ \endverbatim
+*/
+extern SG_EXPORT const char* osgSimGetVersion();
+
+/**
+ * osgSimGetLibraryName() returns the library name in human friendly form.
+*/
+extern SG_EXPORT const char* osgSimGetLibraryName();
+
+}
+
+#endif