Fixing AiiDA tests

[aiida-bot]

Originally reported by: Spyros Zoupanos (Bitbucket: szoup, GitHub: szoupanos)

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The AiiDA tests need fixing:

• The database tests need to work wth SQLAlchemy
• The tests need to return the correct exit code when run (0 for success and something else for failure)
• Various tests that fail should be corrected or deleted if they fail for not the right reason. E.g. some failing tests for the moment: TestCifData, TestStructureData, TestParsers

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• Bitbucket: https://bitbucket.org/aiida_team/aiida_core/issue/276

[aiida-bot]

Original comment by Giovanni Pizzi (Bitbucket: pizzi, GitHub: giovannipizzi):

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Resolved with e2f67de