Pytest-quickcheck

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* support min_length for str data type
* removed distribute dependency
* add pytest-flakes testing

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* fix use the parameter length for string generator even if the set of
available characters is less than it (2)

* support new feature: Generating Collections from sonoflilit

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* the types in the arguments are specified by the types themselves (1)

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* add generating data feature from function annotation

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* first release