Close #18508 -- fix _value2member_map to always have the member's value
Change _names to _names_ since the latter is reserved for Enum use.

Before this change only the methods were _single_underscored_; now
the attributes are as well.
Make the GCC-4.8 compiler happy by moving declarations to the top of the function.
Use strncat() instead of strcat() to silence some warnings.
CID 486616, CID 486617, CID 486615
Fix fishy sizeof(Py_ssize_t *).
sizeof(Py_ssize_t *) == sizeof(Py_ssize_t) but it's not a portable assumption.
CID 486403
Issue #18327: Fix argument order in call to compatible_for_assignment(oldto, newto, attr).
The fix only affects the error message of __class__ assignment. CID 983564
Add missing check of PyDict_SetItem()'s return value in PyEval_EvalCodeEx()
CID 486647
Add missing check of PyDict_SetItem()'s return value in PyEval_EvalCodeEx()
CID 486647
Add missing check of PyDict_SetItem()'s return value in _PyImport_FindExtensionObject()
CID 486649
Add missing check of PyDict_SetItem()'s return value in _PyImport_FindExtensionObject()
CID 486649
Check return value of PyType_Ready(&EncodingMapType)
CID 486654
Check return value of PyType_Ready(&EncodingMapType)
CID 486654
Add missing check of PyDict_SetItem()'s return value
CID 486659
Add missing check of PyDict_SetItem()'s return value
CID 486659
Add missing check of PyDict_Update()'s return value in _elementtree.c
CID 719637
Add missing check of PyDict_Update()'s return value in _elementtree.c
CID 719637
Issue #18513: Add workaround for OS X 10.8 cexp bug that leads to wrong cmath.rect(0.0,-0.0) results.
Issue #18513: Add workaround for OS X 10.8 cexp bug that leads to wrong cmath.rect(0.0,-0.0) results.
Issue #9177: Calling read() or write() now raises ValueError, not AttributeError, on a closed SSL socket.
Patch by Senko Rasic.
test_ssl: use a bytestring here