sharding (core): Add base sharding support.

Add `meta.args` for command line argument access.
Add command line argument support for shard number.
Add shard count to config file.
Add `meta.sharding` exposing shard properties.
Add shard number to logging methods.
Add shard number to data appid.

bot/data/__init__.py

@@ -1,5 +1,5 @@
+from .conditions import Condition, NOT, Constant, NULL, NOTNULL  # noqa
 from .connection import conn  # noqa
 from .formatters import UpdateValue, UpdateValueAdd  # noqa
 from .interfaces import Table, RowTable, Row, tables  # noqa
 from .queries import insert, insert_many, select_where, update_where, upsert, delete_where  # noqa
-from .conditions import Condition, NOT, Constant, NULL, NOTNULL  # noqa

bot/data/conditions.py

@@ -1,5 +1,7 @@
 from .connection import _replace_char
 
+from meta import sharding
+
 
 class Condition:
     """
@@ -82,5 +84,8 @@ class SHARDID(Condition):
         values.append(self.shardid)
 
 
+THIS_SHARD = SHARDID(sharding.shard_number, sharding.shard_count)
+
+
 NULL = Constant('IS NULL')
 NOTNULL = Constant('IS NOT NULL')