Fixed warnings in Bullet/src core library

Thanks Martijn Reuvers from Two Tribes B.V. (www.twotribes.com) for the patch

To make this work more visible, suppress warnings in external libraries in Extras (COLLADA_DOM, libxml and glui contain many warnings)
Added PreprocessorDefinitions: _CRT_SECURE_NO_DEPRECATE;_CRT_NONSTDC_NO_DEPRECATE to vcproj files

src/BulletDynamics/Dynamics/btSimpleDynamicsWorld.cpp

@@ -27,7 +27,11 @@ subject to the following restrictions:
   can be used by probes that are checking whether the
   library is actually installed.
 */
-extern "C" void btBulletDynamicsProbe () {}
+extern "C" 
+{
+	void btBulletDynamicsProbe ();
+	void btBulletDynamicsProbe () {}
+}