Code review comment for lp:~rockstar/entertainer/storage-branch

This branch does a few things. The original reason for this branch was to
define an abstract interface that would stand as the contract for which all
other storage facilities can inherit and implement. This allows Entertainer's
client to know nothing about HOW it's getting its info, and just receive it
based on a storage object implementing this base Storage class. When the
client wants all the music tracks, it just calls storage.music_tracks, and the
storage implementation hides the gory details from the client.

One of my next branches will implement this Storage in a LocalStorage flavor,
allowing me to demonstrate how this will work, and to work out an kinks in the
implementation (and truly there will be).

Along with that, I started consolidating exceptions into the
entertainerlib.exceptions module. This will allow us to keep track of what
types of Exceptions we have already created, so we don't go creating more. I
haven't grabbed all the Entertainer specific exceptions, but I at least wanted
to demonstrate what I was trying to achieve.

There is a lint warning R0921 that is my fault. It's detected that Storage is
an abstract class and lets me know I haven't implemented it anywhere.
Apparently pylint doesn't like disabling of the refactoring warnings, and since
it's a temporary warning, I thought we could let it slide. If you as the
reviewer feel I should do something about it, then I'll probably create an
empty class that "implement" Storage for now.

--
Paul Hummer
http://theironlion.net
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