Switch autoloader from PSR-0 to PSR-4
minor #32 Switch autoloader from PSR-0 to PSR-4 (jmgq)

This PR was squashed before being merged into the 1.0-dev branch (closes #32).

Discussion
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Switch autoloader from PSR-0 to PSR-4

Autoloading was changed to PSR-4, as requested in #26.

Commits
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89e4b4d Switch autoloader from PSR-0 to PSR-4