'mode' docs fix: the file must always be opened in binary in Python3.

Bug in Wave_write.close: when the close method calls the check that the header
exists and it raises an error, the _file attribute never gets set to None, so
the next close tries to close the file again and we get an ignored traceback
in the __del__ method.  The fix is to set _file to None in a finally clause.
This represents a behavior change...in theory a program could be checking for
the error on close and then doing a recovery action on the still open file and
closing it again.  But this change will only go into 3.4, so I think that
behavior change is acceptable given that it would be pretty weird and unlikely
logic to begin with.

    warning: 'utime.mtime_ns' may be used uninitialized in this function [-Wmaybe-uninitialized]

    warning: 'utime.mtime_ns' may be used uninitialized in this function [-Wmaybe-uninitialized]

Issue #18214: Improve finalization of Python modules to avoid setting their globals to None, in most cases.

Issue #15699: The readline module now uses PEP 3121-style module initialization, so as to reclaim allocated resources (Python callbacks) at shutdown.
Original patch by Robin Schreiber.

Feature and tests by ClClaudiu.Popa, I added the doc changes.

gcov is great.

CID 1058763

"coverage-report" creates an instrumented Python build, runs unit tests
and creates a HTML. The report can be updated with "make coverage-lcov".

Patch by Sijin Joseph.

testcleanup directive is new as of 1.1, and we are currently running
1.0.7.  But using testsetup works just as well, and avoids the
unknown directive error when building the docs.

'SHA1' instead of 'SHA'.
Add more tests for hashlib and hash object attributes

'SHA1' instead of 'SHA'.