Move warning check in `get_cache_path` to follow directory creation. Fixes #375.

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branch : distribute
Merge another fix for regressions brought about by #375.

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branch : distribute
Added tag 0.6.49 for changeset f657df1f1ed4

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branch : distribute
Bumped to 0.6.50 in preparation for next release.

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branch : distribute
Merge with Distribute 0.6.49

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rename : distribute_setup.py => ez_setup.py
Update changelog