Per PEP 600:
```
When this PEP is accepted, the previous manylinux PEPs will receive a final update noting that they are no longer maintained and referring to this PEP.
```
Changes detected by Topy (https://github.com/intgr/topy), all changes
verified by hand, false positives have been omitted.
These range from straight-out misspellings to debatable hyphen placement.
The hyphen changes are supported by grammar manuals of style.
Following popular demands over at manylinux, the `i686` image was updated to use the same `devtoolset-8` as the `x86_64` image.
`devtoolset-8` was not included in the first place because was not available anywhere for `i686`. We're now rebuilding it on COPR to address concerns expressed in the manylinux repo about this software stack inconsistency.
Matching the symbols permitted for x86_64 by GCC_4.3.0 require a limit of GCC_4.5.0 on i686 CentOS 6.
This does create the risk that 32-bit extension modules using `__extendxftf2` may not actually be portable to all 2010 era systems, but most of those other than RHEL/CentOS 6 have already hit the end of their respective support periods.
manylinux1 is getting old enough now to start making things
difficult (specifically around network security), so it's time
for a refresh to a slightly newer baseline.