v1.1.0

Minor Changes:

• workerpool: add Len() to retrieve the count of running workers (#21, @kaworu)

Other Changes:

• .github: run tests on Go 1.17 (#27, @tklauser)
• .github: show diff when gofmt check fails (#20, @tklauser)
• ci: use golangci-lint for static checks (#28, @rolinh)
• ci: use latest versions (#26, @rolinh)
• Fail TestWorkerPoolLen if (*WorkerPool).Close fails (#24, @tklauser)
• Move example to the workerpool_test package (#25, @rolinh)
• Move tests into a separate package (#22, @tklauser)
• Run staticcheck as part of CI (#19, @tklauser)
• Test (*WorkerPool).Len after Close (#23, @tklauser)