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/meta/__init__.py

@@ -1,3 +1,5 @@
+from .logger import log, logger
 from .client import client
 from .config import conf
-from .logger import log, logger
+from .args import args
+from . import sharding