Added administration.lua.

Adds self-hosted, single-realm administrative functions to otouto.
Check out the README for a detailed description.

Also added msg.from.name, which is msg.from.first_name + msg.from.last_name (if it
exists), because I'm too lazy to build it each time.
Fixed a crash-causing bug (ironically) in the handle_exception() function.

launch.sh

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/bin/sh
 
 while true; do
 	lua bot.lua