Amend PEP440 to limit version identifiers

PEP440 does not contain a limit for version ids. Can we please add one? things like uselesscapitalquiz · PyPI happen without it, and other issues arise not least of which is user a11y related to trying to fit/show all of the wild versioning stats from pypi: we have 9.9mm releases, median version is 5 characters, 99th percentil is 20, and maximal is 217(!!) I propose a 128 char cap, 100 would affect ~9 current releases some releases in the last months with ~110-115 char versioning which I ho...