Log Message:
py37-html-docs: Update lang/py37-html-docs to 3.7.1

Changes:
3.7.1
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Documentation
=============
- bpo-32174: chm document displays non-ASCII charaters properly on some
             MBCS Windows systems.
- bpo-34790: Document how passing coroutines to asyncio.wait() can be
             confusing.
- bpo-28617: Fixed info in the stdtypes docs concerning the types that
             support membership tests.
- bpo-34065: Fix wrongly written basicConfig documentation markup syntax
- bpo-33460: replaced ellipsis with correct error codes in tutorial
             chapter 3.
- bpo-33847: Add `@' operator entry to index.
- bpo-25041: Document AF_PACKET in the socket module.