feat design 功能迁移

app/service/design/items/builder.py

@@ -0,0 +1,9 @@
+from mmcv.utils import Registry, build_from_cfg
+
+ITEMS = Registry('item')
+PIPELINES = Registry('pipeline')
+
+
+def build_item(cfg, default_args=None):
+    item = build_from_cfg(cfg, ITEMS, default_args)
+    return item