Refactor Bot.send* methods and fix #35
Refactor Bot.send* methods and fix #35

Because those methods were identical, this commit generates them
dynamically right after the class definition, and appends them to the
class.

This also fixes an exeception when you send a message to a channel with
the Bot.send* methods (issue #35).

thesharp/botogram,pietroalbini/botogram,pietroalbini/botogram,thesharp/botogram