Move findNodeNearTarget function from path to pathnavigator

To reduce conflicts between wisdome installation branch and master

include/openspace/navigation/pathnavigator.h

@@ -80,6 +80,13 @@ public:
 
     const std::vector<SceneGraphNode*>& relevantNodes();
 
+    /**
+    * Find a node close to the given node. Closeness is determined by a factor times
+    * the bounding sphere of the object
+    * \return pointer to the SGN if one was found, nullptr otherwise
+    */
+    static SceneGraphNode* findNodeNearTarget(const SceneGraphNode* node);
+
     /**
     * \return The Lua library that contains all Lua functions available to affect the
     * path navigation