[Refactor] Refactor code structure and docstrings (#803)

* refactor points_in_boxes

* Merge same functions of three boxes

* More docstring fixes and unify x/y/z size

* Add "optional" and fix "Default"

* Add "optional" and fix "Default"

* Add "optional" and fix "Default"

* Add "optional" and fix "Default"

* Add "optional" and fix "Default"

* Remove None in function param type

* Fix unittest

* Add comments for NMS functions

* Merge methods of Points

* Add unittest

* Add optional and default value

* Fix box conversion and add unittest

* Fix comments

* Add unit test

* Indent

* Fix CI

* Remove useless \\

* Remove useless \\

* Remove useless \\

* Remove useless \\

* Remove useless \\

* Add unit test for box bev

* More unit tests and refine docstrings in box_np_ops

* Fix comment

* Add deprecation warning

mmdet3d/models/roi_heads/h3d_roi_head.py

@@ -65,15 +65,15 @@ class H3DRoIHead(Base3DRoIHead):
             feats_dict (dict): Contains features from the first stage.
             img_metas (list[dict]): Contain pcd and img's meta info.
             points (list[torch.Tensor]): Input points.
-            gt_bboxes_3d (list[:obj:`BaseInstance3DBoxes`]): Ground truth \
+            gt_bboxes_3d (list[:obj:`BaseInstance3DBoxes`]): Ground truth
                 bboxes of each sample.
             gt_labels_3d (list[torch.Tensor]): Labels of each sample.
-            pts_semantic_mask (None | list[torch.Tensor]): Point-wise
+            pts_semantic_mask (list[torch.Tensor]): Point-wise
                 semantic mask.
-            pts_instance_mask (None | list[torch.Tensor]): Point-wise
+            pts_instance_mask (list[torch.Tensor]): Point-wise
                 instance mask.
-            gt_bboxes_ignore (None | list[torch.Tensor]): Specify
-                which bounding.
+            gt_bboxes_ignore (list[torch.Tensor]): Specify
+                which bounding boxes to ignore.
 
         Returns:
             dict: losses from each head.