Log Message:
py-pluggy: updated to 0.6.0

0.6.0
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Add CI testing for the features, release, and master branches of pytest.
Document public API for _Result objects passed to wrappers.
Document and test hook LIFO ordering.
Turn warnings into errors in test suite.
Deprecate _Result.result.
Convert _Multicall to a simple function distinguishing it from the legacy version.
Resolve E741 errors.
Test and bug fix for unmarked hook collection.
Drop support for EOL Python 2.6 and 3.3.
Fix inspect based arg introspection on py3.6