Generate road network

This package generates simple road network from edge image

What it does:

classify inner and outer region of the road (useful for drivable map generation) (enabled with mark_inner_region in the config file)
cover the inner region with discs and generate route graph (Reference: Reconstructing Road Network Graphs from both Aerial Lidar and Images) (enabled with generate_graph in the config file)

The route graph is still very simple (not directed, not free of cycles)

Explanation of some parameters:

bag_path: this is the trajectory used to propose candidates for inner region image. Should contain topic_name, expected to be of type Odometry
inner_image_path: this is the input to graph generation step, which could be the output of the first step or output of the first step with some modification (erosion, manual cleanup, etc)