Use vendoring for backward compatibility
The switch of the Madon library to Go modules breaks builds with
Go version < 1.11 since the import path now contains "v2".
This patch adds vendoring so that it can still build with those
versions.
Let's try to re-enable Travis builds with Go v1.8-1.11...
module github.com/McKael/madonctl
require (
github.com/BurntSushi/toml v0.3.1 // indirect
github.com/McKael/madon/v2 v2.3.1-0.20180929094633-c679abc985d6
github.com/cpuguy83/go-md2man v1.0.9-0.20180619205630-691ee98543af // indirect
github.com/ghodss/yaml v1.0.0
github.com/inconshreveable/mousetrap v1.0.0 // indirect
github.com/kr/pretty v0.1.0 // indirect
github.com/kr/text v0.1.0
github.com/mattn/go-isatty v0.0.4
github.com/pkg/errors v0.8.0
github.com/russross/blackfriday v2.0.0+incompatible // indirect
github.com/shurcooL/sanitized_anchor_name v0.0.0-20170918181015-86672fcb3f95 // indirect
github.com/spf13/cobra v0.0.3
github.com/spf13/pflag v1.0.2
github.com/spf13/viper v1.2.1
github.com/stretchr/testify v1.2.2
golang.org/x/net v0.0.0-20180926154720-4dfa2610cdf3
golang.org/x/sys v0.0.0-20180928133829-e4b3c5e90611 // indirect
gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127 // indirect
)