rewrite: Initial rewrite skeleton.

Remove modules that will no longer be required.
Move pending modules to pending-rewrite folders.

bot/modules/pending-rewrite/study/badges/data.py

@@ -0,0 +1,24 @@
+from cachetools import cached
+
+from data import Table, RowTable
+
+study_badges = RowTable(
+    'study_badges',
+    ('badgeid', 'guildid', 'roleid', 'required_time'),
+    'badgeid'
+)
+
+current_study_badges = Table('current_study_badges')
+
+new_study_badges = Table('new_study_badges')
+
+
+# Cache of study role ids attached to each guild. Not automatically updated.
+guild_role_cache = {}  # guildid -> set(roleids)
+
+
+@study_badges.save_query
+@cached(guild_role_cache)
+def for_guild(guildid):
+    rows = study_badges.fetch_rows_where(guildid=guildid)
+    return set(row.roleid for row in rows)