Coersion to subclasses prefered in overload resolution to coersion to nullptr_t.

These are usually errors, and this is useful debug information to have.
It can still be disabled via a directive.

Typo

Removing stray text.

This is better than generating invalid code; see #1695.

pyximport: remove obsolete version check

The file is syntactically correct only in Python >= 2.6, so the
version check would never be run.

This fixes #1702.

Support pickling of cdef classes.

Fix profiling for generators and generator expressions

Previously, if incrementing by the length failed to make the
index positive, this *incremented* index was passed in an attempt
to raise the correct error.

This fixes #1700.

Now uses specialised functions for complex abs

Print no message if force=True

Closes #1664

add a compile test for github issue #1692: raising StopAsyncIteration without using "await" was missing utility code and failed to compile

Closes #1692

use different codec alias names in test code than in optimiser code to check that the alias name resolution works

Repair incorrect C-API signature usage for PyUnicode_DecodeUTF16() when optimising bytes decoding from UTF-16(LE/BE)

Closes #1696

Remove obsolete documentation

Fix bad indentation in a pyximport test

The indentation was inadvertently broken when expanding tabs in
e908c0b9.

Fixes:

    $ python pyximport/test/test_reload.py
      File "pyximport/test/test_reload.py", line 23
        assert hello.x == 1
        ^
    IndentationError: unexpected indent

Fix incorrect use of flags in re.sub()