devel/py-pytest-timeout: Update to 1.3.1

[loader]

Summary

Proposed commit log message:

devel/py-pytest-timeout: Update to 1.3.1

Changelog:
  https://bitbucket.org/pytest-dev/pytest-timeout/commits/17415e95a83386e2b4dba12b995ce13bd0dbdb6b?at=1.3.1#chg-README

- Update PORTVERSION and distinfo checksum to 1.3.1
- Add a patch to fix build with Python 3.x in the C locale [0]

[0] https://bitbucket.org/pytest-dev/pytest-timeout/pull-requests/15/use-utf-8-encoding-to-open-the-readme-file/

Reviewed_by: koobs
Approved by: koobs (mentor)
Differential_Revision: D16567

Test Plan

• portlint: OK (looks fine.)
• testport: OK (poudriere: 1200075, [armv7, aarch64], 'BUILD_ALL_PYTHON_FLAVORS=1', [py27, py34, py35, py36, py37] tested)
• unittest: OK (

Python2.7 on aarch64: 34 passed, 1 xfailed
Python3.4 on aarch64: 34 passed, 1 xfailed
Python3.5 on aarch64: 34 passed, 1 xfailed
Python3.6 on aarch64: 34 passed, 1 xfailed
Python3.7 on aarch64: 1 failed, 34 passed
)

[koobs]

LGTM, thanks @loader!

[loader]

Thanks @koobs.