Direct all test output in the test runner to stderr because that's where unittest is writing it, and it gives better ordering on Windows to not mix stdout and stderr.

Allow explicit "-2" option for the cythonize script to set the language level to 2 (the current, but not future, default).

Remove docs note about fused types being "experimental". They are old enough by now to consider them an established language feature.

Avoid depending on some C macros in the buildenv.pyx test that might not be defined (specifically on MSVC, as usual).

Added basic ctuple documentation.

Extend "buildenv" test to show more information about the build system, including the distutils configuration.

Closes #2567.

Fix overflow.fold being available on most directives in pure python mode

Add export of the bytearray cpython api

Fix usage of special name "sizeof" in a test: cannot be assigned to a variable because it is not an actual function.