[Feature] Implement LiDAR Pipeline

[Ulixes-8]

Description

The LiDAR pipeline is the 3D object detection pipeline for the AV. It includes:

• LiDAR-based 3D object detection.
• LiDAR clustering (for downstream camera-LiDAR fusion).
• The elimination of false positive 3D object detections with help from the Occupancy Grid Map Pipeline.

Checklist
Write a launch file that successfully launches:

• The Occupancy Grid Map Pipeline.
• LiDAR-based 3D object detection.
• LiDAR clustering.
• Occupancy grid map-based validation.

Acceptance Criteria

As confirmed by testing:

• LiDAR-based 3D object detection module takes in PointCloud2 messages and outputs DetectedObjects.
• The occupancy grid map-based validator takes in DetectedObjects from LiDAR-based 3D object detector and the occupancy grid from the occupancy grid map pipeline.
• The occupancy grid map-based validator outputs DetectedObjects with eliminated false positive predictions.
• LiDAR clustering takes in PointCloud2 messages and outputs DetectedObjectsWithFeatures.

Priority
High (3/3)