[Checkins] [zopefoundation/zope.interface] d88017: Always build manylinux wheels

[Marius Gedminas]

  Branch: refs/heads/modernize-ci
  Home:   https://github.com/zopefoundation/zope.interface
  Commit: d88017c2c7af09dbd1a82dfbf9e21b1b71dae6ba
      https://github.com/zopefoundation/zope.interface/commit/d88017c2c7af09dbd1a82dfbf9e21b1b71dae6ba
  Author: Marius Gedminas <marius at gedmin.as>
  Date:   2019-11-11 (Mon, 11 Nov 2019)

  Changed paths:
    M .manylinux-install.sh
    M .manylinux.sh
    M .travis.yml

  Log Message:
  -----------
  Always build manylinux wheels

This PR makes it so we _always_ build manylinux wheels, but only upload
them for git tags.

Highlights:

- Move regular Linux Python builds outside the build matrix, for
  conciseness.

- Switch manylinux1 builds to manylinux2010 (they should still get the
  manylinux1 tag if they're compatible, but they'll be built with a more
  modern compiler toolchain).

- Move twine upload from .manylinux.sh into .travis.yml's after_success,
  right next to the twine upload used for Mac OS builds.

- This means we can't short-circuit the builds with 'exit 0' in
  before_install:, so overwrite the install: and script: sections too.

- Move the 'docker pull' from .manylinux.sh into the install: section
  so it's not empty.

- Provide twine credentials via environment variables instead of
  command-line/pypirc file.

- Put related commands inside a single multiline if statement.

- Use setup.py -q test (quiet build) instead of setup.py test -q (which
  does nothing at all AFAICT).

This mirrors changes made to other zopefoundation packages tracked in
https://github.com/zopefoundation/meta/issues/11.