Document that ctypes automatically applies byref() when argtypes declares
POINTER.

Previously the parts of the message retained whatever linesep they had on
read, which means if the messages weren't read in univeral newline mode, the
line endings could well be inconsistent.  In general sending it via smtplib
would result in them getting fixed, but it is better to generate them
correctly to begin with.  Also, the new send_message method of smtplib does
not do the fixup, so that method is producing rfc-invalid output without this
fix.

#11732: add a new suppress_crash_popup() context manager to test.support that disables crash popups on Windows and use it in test_ctypes.

response message when  send_error includes a message in addition to error
status. Patch contributed by Karl.

Issue #17278: Fix a crash in heapq.heappush() and heapq.heappop() when the list is being resized concurrently.

Fix issue16932: Fix the urlparse example. Remote :port when scheme is not specified to demonstrate correct behavior

This fixes an apparent copy-and-paste error.

Patch by Manuel Jacob.

Patch by Lowe Thiderman

#15438: add a note to math.pow() that suggests using **/pow() for integers.  Patch by Mark Dickinson.