Travis CI Windows

[zmughal]

From https://blog.travis-ci.com/2018-10-11-windows-early-release:

Windows is available right now to everyone with open-source and private projects on either travis-ci.org or travis-ci.com, with plans to bring it to Enterprise soon. This is our very first full approach to Windows-support, so the tooling is light - and we want your feedback on our community forum. Come get started!

[zmughal]

• https://github.com/theory/winperl-travis
• https://travis-ci.community/t/feedback-from-windows-integration-for-a-cmake-qt-c-python-perl-project/1706
• https://travis-ci.community/t/refreshenv-for-bash/3753/2
• https://github.com/jwbargsten/perl-proc-processtable/pull/26/files