rename ObsoleteDemos back to Demos

fix some relative path issues for loading assets

Demos/TerrainDemo/main.cpp

@@ -0,0 +1,14 @@
+
+#include "TerrainDemo.h"
+#include "GlutStuff.h"
+
+int main(int argc,char** argv)
+{
+	DemoApplication * demo = btCreateTerrainDemo();
+	btAssert(demo && "failed to create terrain demo object");
+
+        return glutmain(argc, argv, 800, 600,
+	    "Terrain Demo. http://www.continuousphysics.com/Bullet/phpBB2/",
+	    demo);
+}
+