No Windows CI configuration

[AlekSi]

Only Windows CI configuration is left. Open third-party issues:

• https://github.com/client9/shlib/issues/3#issuecomment-435660161
  • https://github.com/client9/shlib/issues/13
  • https://github.com/client9/shlib/pull/14

[AlekSi]

We now have a Travis CI configuration:

• https://github.com/gosh-lang/gosh/blob/master/.travis.yml
• https://travis-ci.org/gosh-lang/gosh

~AppVeyor builds are enabled: https://ci.appveyor.com/project/AlekSi/gosh~ I disabled them to debug a separate issue with codecov.io. However, anyone can enable them for their own fork. We need to add a configuration file for it. Help wanted. One example of a Go project with builds on AppVeyor is reform: https://github.com/go-reform/reform/blob/v1-stable/appveyor.yml But we probably will need something much easier.

[AlekSi]

We also should enable macOS configurations on Travis CI.

[AlekSi]

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

[AlekSi]

Waiting for those issues to be resolved:

• https://github.com/client9/shlib/issues/13
• https://github.com/golangci/golangci-lint/issues/338
• https://github.com/goreleaser/goreleaser/issues/933