Patch from Victor van den Elzen.

Ignore pip warning in test_venv.test_with_venv().

Issue #17758: Skip test_site if site.USER_SITE directory doesn't exist and
cannot be created.

#25687: clarify that errors in tearDown increase the total number of reported errors.  Initial patch by HyeSoo Park.

Tamás Bence Gedai.

Patch by Dmitry Shachnev.

NotImplementedError instead of ImportError.

multipliers, not final sizes.  Explain y default for .zoom and .subsample.
Initial patch by Serhiy Storchaka.

* add link to PYTHONMALLOCSTATS env var
* add parameters to PyMem macros like PyMem_MALLOC()
* fix PyMem_SetupDebugHooks(): add Calloc functions
* add some newlines for readability

Added few missed tests for configure options.

Force clean of externals on buildbots.

The bufsize parameter is no longer used.

On Windows a symlink can has the FILE_ATTRIBUTE_DIRECTORY flag.

On Windows a symlink can has the FILE_ATTRIBUTE_DIRECTORY flag.

gcc as the option does not work correctly in older versions of gcc
and has been silently removed as of gcc-4.5.

Patch by Alex Willmer.

Since Python 3.4, there is no need to install pip and setuptools
into a venv manually.

Patch by Guo Ci Teo.

Raise ValueError if algorithm is not MD5 or SHA.

Initial patch by Mathieu Dupuy.