rewrite: New Video channels and moderation.

src/modules/video_channels/data.py

@@ -0,0 +1,7 @@
+from data import Registry, Table
+
+
+class VideoData(Registry):
+    video_channels = Table('video_channels')
+    video_exempt_roles = Table('video_exempt_roles')
+    video_blacklist_durations = Table('studyban_durations')