Integrate Faker library.

Integrated the Fzaninotto/Faker for easier generation of fake fixture
data.
Remove Singleton, alllow Constructor DI.

Removed the parent Singleton class that the Fixture class was inheriting
from (it was unnecessary).  Updated Fixture to allow constructor
injection when first creating a fixture instance.
Make fake method static.

The fake method has now been made static in order to provide an easier
interface for using faker inside fixtures.
Move truncate method to abstract class.

Moved the truncate method into the abstrct Repository class so that it
can be re-used by all repositories.
Tighten up test suite.

Added more tests to the test suite to ensure correctness of code.
Update files for version 1.0.0.

Updated README.md, composer.json, and fixture.php files in preparation
for a 1.0.0 release.