Allow install to proceed with an egg install on IronPython and any other environment that has no stack support. Fixes #177.

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extra : amend_source : c92063405d99e7fdb7fe0a6312fa8438c3727c2f

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extra : amend_source : 829ebde0696d12adfb54aca74ea6b1b510177ff4

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extra : amend_source : 62f689b409b4645eda5f81b2604c50a84713ee52

Removed notice about PEP 420 package finder. Discussion in the ticket (Ref #97) indicates that the implementation is currently inadequate.

Just remove test_ez_setup, as the last remaining test, test_install, only barely touches the functionality as the actually installation command is mocked. The test run in the travis config is much more comprehensive.

Remove test for use_setuptools, as it fails when running under pytest because the installed version of setuptools is already present.

Remove test_build_egg. The test doesn't work and it's difficult to test _build_egg given the current interface.

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extra : amend_source : eb261716fc15148a101c059fb03c0f51b683c673

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extra : amend_source : d60530fbb3e3cc3455abae8e5100f85f697f3dac