Optimized reversed range with constant negative steps.

extend reversed iteration tests, including disabled tests for negative step values that fail when enabled

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extra : transplant_source : %F9%BB%B7%FD%A5jc%89%02%BD%BANie%A3%FDc%8F%9Ct

Use PySequence_List, PySequence_Tuple

Cython array import naming conflict

do not depend on reversed(range()) bounds having a numeric type and just use whatever spanning type we find

Optimized reversed-range call when constants are inside of the range.

postpone import of distutils Extension type in test runner in case setuptools gets imported in between

postpone import of distutils Extension type in test runner in case setuptools gets imported in between

--HG--
extra : transplant_source : %9B%C2%08Q%DDt%9A%99%A4%CAK%5D%8F%3A%A9%E4F%19%96%CD

fix test runner and pyximport in Py 2.7.9 and 3.4+: setuptools replaces "distutils.dist.Distribution" *after* we import it, which then breaks the input validation in "distutils.cmd"

fix test runner and pyximport in Py 2.7.9 and 3.4+: setuptools replaces "distutils.dist.Distribution" *after* we import it, which then breaks the input validation in "distutils.cmd"

--HG--
extra : transplant_source : %3A%84%AC%02E%17%D8%EE%E64Mpv%25%A3%8E%8B%E5%CA%19

Minor cleanup (2.5 compat, mostly)

optimize general sorted(x) calls

fix shrinking and overflow in cpython.array

optimize sorted([a,b,c]) into PyList_Sort call

Emit DL_IMPORT macro for python3