Add URL shortener to urlparse. Fixes #14

Uses goo.gl API anonymously.
Also cleaned up the code a little.
Make shortcut for channel or user. Empty Template.

Choosing whether the intended target for messages,
either the channel or the user, for commands that do both
was common enough to incorporate into the base class.
From now on, using self.target is a sane default.

Also added an empty module template.