Restructuring for OpenSpace tests

- Moved all OpenSpace headers to separate include directory
- Added OpenSpaceTests binary with OPENSPACE_HAVE_TESTS define
- Added CMake setting of BASE_DIR
- Added OpenSpace initial tests for SceneGraph and SceneGraphNodes
- Added OpenSpace initial tests for psc and pss
- Restructured OpenSpace so no GL functions are called in constructors
to make the classes testable

- Todo: Make the base dir possible to set through command line argument
and configuration file

include/openspace/rendering/renderablebody.h

@@ -0,0 +1,37 @@
+#ifndef RENDERABLEBODY_H
+#define RENDERABLEBODY_H
+
+// open space includes
+#include <openspace/rendering/renderable.h>
+#include <openspace/util/sphere.h>
+
+// ghoul includes
+#include "ghoul/opengl/programobject.h"
+#include "ghoul/opengl/texture.h"
+
+namespace openspace {
+/*
+class RenderableBody: public Renderable {
+public:
+
+	// constructors & destructor
+	RenderableBody(const pss &radius);
+	~RenderableBody();
+
+	void setProgramObject(ghoul::opengl::ProgramObject *programObject);
+	void setTexture(ghoul::opengl::Texture *texture);
+
+	virtual void render(const Camera *camera, const psc &thisPosition);
+	virtual void update();
+
+private:
+	ghoul::opengl::ProgramObject *programObject_;
+	ghoul::opengl::Texture *texture_;
+	double rad_;
+
+	gl4::Sphere *planet_;
+};
+*/
+} // namespace openspace
+
+#endif