Use fixtures in the unit tests

This is The Good Stuff. The entire test suite can now be run without
having to setup a database, running the batch checker, any of the web
services or the website. It even passes without an internet connection.
In, like, 30 seconds! Awesome!

This means tests don't randomly fail after some reference sequence
changes on the NCBI server and it doesn't take an entire configured
server with mapping database setup to run the tests. Those are things
of the past! No more frustrations, Mutalyzer is testable!

Going down now...

The mountain screamed three times today
I guess it thought it'd like to play
How much does one have to pay
To fry a peak and melt away
Launching titan's breath on mine
The sweating measure lands on time

And the old man, down by the river
Well he walks up and he walks on down
To the spaceship that's parked at your doorstep
And it's waiting to take you away now

Goin' down now
Goin' down now

Looking for the rate that crowed
He's hooked up down in Mexico
Slap my nerve now give me more
It's my disaster friend, not yours

And the old man, down by the river
Well he walks up and he walks on down
To the spaceship that's parked at your doorstep
And it's waiting to take you away now

And the last one, it's down by the river
Where he gets up and he walks on down
To the spaceship that's parked at your doorstep
And it's waiting to take you away now

It's down by the river, it's always this way now
It's down by the river, it's always this way now

Going down now
Going down now
now, now, now

down, down, down