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

Demos/CharacterDemo/CharacterDemo.cpp

@@ -307,11 +307,8 @@ const float TRIANGLE_SIZE=20.f;
 //to be implemented by the demo
 void CharacterDemo::renderme()
 {
-	
 	updateCamera();
 
-	btScalar m[16];
-	int i;
 	DemoApplication::renderme();
 }