Issue #17176: Document that imp.NullImporter is no longer
automatically used by import.
#17307 - Example of HTTP PUT Request using http.client
#17307 - merge from 3.2
Issue #17386 make.bat must run with Python 2 until Sphinx runs with Python 3.
If PYTHON is undefined, this fails without the launcher (installed with 3.3 or
from PyPI), but this is better than always failing. Patch from Zachary Ware.
Merge with 3.2: Issue #17386