Feature/interactionsphere (#1561)

* Add ability to render the bounding sphere as a debug option
* Separate boundingsphere and interactionspheres
* Correctly compute BoundingSpheres for more renderables (RenderablePlanesCloud, RenderableOrbitalKepler)

include/openspace/util/updatestructures.h

@@ -50,7 +50,7 @@ struct UpdateData {
 struct RenderData {
     const Camera& camera;
     const Time time;
-    int renderBinMask = -1;
+    int8_t renderBinMask = -1;
     TransformData modelTransform;
 };