[3.6] bpo-35564: add master_doc='contents' to conf.py (GH-11290). (GH-12461)

Fix "catchs" typos in NEWS entries (GH-12366)

bpo-36195: Remove the ThreadPoolExecutor documentation mentioning the initializer feature added in Python 3.7 (GH-12182)

bpo-34745: Fix asyncio sslproto memory issues (GH-12386)

bpo-36272: Logging now propagates RecursionError (GH-12312)

[3.6] bpo-36216: Add check for characters in netloc that normalize to separators (GH-12201) (GH-12215)