Composer fixes and updated the autoloading
feature #74 Composer fixes and updated the autoloading (GrahamCampbell)

This PR was squashed before being merged into the master branch (closes #74).

Discussion
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Composer fixes and updated the autoloading

PSR-0 is deprecated, and we should also be autoloading our tests in `autoload-dev`. We can easily move to PSR-4 without moving any of the files thus retaining bc for any people still requiring files manually. Let me know if you're fine with actually just moving the files up 2 levels in the interest of keeping things clean.

Commits
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e85d5b4 Composer fixes and updated the autoloading