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/args.py

@@ -0,0 +1,19 @@
+import argparse
+
+from constants import CONFIG_FILE
+
+# ------------------------------
+# Parsed commandline arguments
+# ------------------------------
+parser = argparse.ArgumentParser()
+parser.add_argument('--conf',
+                    dest='config',
+                    default=CONFIG_FILE,
+                    help="Path to configuration file.")
+parser.add_argument('--shard',
+                    dest='shard',
+                    default=None,
+                    type=int,
+                    help="Shard number to run, if applicable.")
+
+args = parser.parse_args()