This does two things. Most notably, it adds MySQL to SecureDrop. This is
necessary for the generation of source designations by the journalist.
HACKING.md and setup_ubuntu.sh have both been modified to add this piece
of infrustructure. setup_ubuntu requires no additional user input for
this step, and modifies config.py accordingly.

This adds an additional 2 pip dependencies:
MySQL-python
SQLAlchemy

The db.py module uses SQLAlchemy to define the tables and perform
database functions.

We are storing the codenames in the database which can be queried with
the sid.

New codenames are generated with two new dictionaries, located in
deaddrop/dictionaries, with an adjective and noun pair. This is
memorable for the journalist. These dictionaries were generated with the
python natural language toolkit, using the wordnik database.
Merge branch 'feature/issue95' of https://github.com/Hainish/securedrop into Hainish-feature/issue95

Conflicts:
	.gitignore
	securedrop/example_config.py
	setup_ubuntu.sh

This merge changes the default database settings so mysql is not required for
development (use the built-in sqlite instead). It also integrates the database
with the tests, using a temporary sqlite database instead of re-using an
existing databsae, which could cause problems.

If you experience errors related to missing tables after updating, make sure
you've updated your config with the database settings, then run `python -c
"import db; db.create_tables()"`.
Merge branch 'Hainish-feature/issue95'
make sqlite the default database

I lied in the previous merge commit's message. This commit actually makes
sqlite the default database. This reduces the number of dependencies for the
development environment because sqlite is included with Python.
clean up dev setup script, config, and .gitignore