Added a basic COLLADA .dae importer mainly to support URDF loading (URDF can refer to COLLADA .dae or STL .stl for mesh support)

It is fairly limited, only supports loading <geometry> with triangulated meshes, no material loading
I will extend this with COLLADA Physics support.

Demos3/ImportColladaDemo/LoadMeshFromCollada.h

@@ -0,0 +1,35 @@
+/*
+Bullet Collision Detection and Physics Library http://bulletphysics.org
+This file is Copyright (c) 2014 Google Inc. 
+
+This software is provided 'as-is', without any express or implied warranty.
+In no event will the authors be held liable for any damages arising from the use of this software.
+Permission is granted to anyone to use this software for any purpose,
+including commercial applications, and to alter it and redistribute it freely,
+subject to the following restrictions:
+
+1. The origin of this software must not be misrepresented; you must not claim that you wrote the original software. If you use this software in a product, an acknowledgment in the product documentation would be appreciated but is not required.
+2. Altered source versions must be plainly marked as such, and must not be misrepresented as being the original software.
+3. This notice may not be removed or altered from any source distribution.
+
+//original author: Erwin Coumans
+*/
+
+
+#ifndef LOAD_MESH_FROM_COLLADA_H
+#define LOAD_MESH_FROM_COLLADA_H
+
+#include "LinearMath/btAlignedObjectArray.h"
+#include "LinearMath/btTransform.h"
+#include "OpenGLWindow/GLInstanceGraphicsShape.h"
+#include "ColladaGraphicsInstance.h"
+
+
+void LoadMeshFromCollada(const char* relativeFileName,
+						btAlignedObjectArray<GLInstanceGraphicsShape>& visualShapes, 
+						btAlignedObjectArray<ColladaGraphicsInstance>& visualShapeInstances,
+						btTransform& upAxisTrans,
+						float& unitMeterScaling);
+
+
+#endif //LOAD_MESH_FROM_COLLADA_H