[Fix] Fix all unittests and refactor tests directory and add circle ci in `test-1.x` (#1654)

* add circle ci

* delete github ci

* fix ci

* fix ut

* fix markdown version

* rm

* fix part of uts

* fix comments

* change foler

* refactor test directory

* fix kitti metric ut

* fix all ut
Co-authored-by: VVsssssk <shenkun@pjlab.org.cn>

mmdet3d/datasets/transforms/loading.py

@@ -288,6 +288,20 @@ class PointSegClassMapping(BaseTransform):
     others as len(valid_cat_ids).
     """
 
+    def __init__(self, valid_cat_ids, max_cat_id=40):
+        assert max_cat_id >= np.max(valid_cat_ids), \
+            'max_cat_id should be greater than maximum id in valid_cat_ids'
+
+        self.valid_cat_ids = valid_cat_ids
+        self.max_cat_id = int(max_cat_id)
+
+        # build cat_id to class index mapping
+        neg_cls = len(valid_cat_ids)
+        self.cat_id2class = np.ones(
+            self.max_cat_id + 1, dtype=np.int) * neg_cls
+        for cls_idx, cat_id in enumerate(valid_cat_ids):
+            self.cat_id2class[cat_id] = cls_idx
+
     def transform(self, results: dict) -> None:
         """Call function to map original semantic class to valid category ids.