Core user data and leaderboard commands.

Added flexibility to data `update_where`.
Added interactive utils, with improved pager.
Added user data table, with caching and transactional interface.
Added `topcoins` command to `Economy`
Added `top` command to `Study`

bot/modules/__init__.py

@@ -1 +1,3 @@
 from .sysadmin import *
+from .economy import *
+from .study import *