Version 3

With this version it is possible to load trigulated mesh objects (in .obj). Our DIY renderer can do wireframe rendering of mesh objects. If running surfel_fusion node, branch VINS_kidnapping (https://github.com/HKUST-Aerial-Robotics/DenseSurfelMapping), this node can estimate the ground plane and compute the ground orientation with respect to the camera

This version can subscribe to path messages from kidnap aware pose graph solver(https://github.com/mpkuse/solve_keyframe_pose_graph). This allows us to do correct rendering even under kidnaps.