Add Makefile and licence to version output

Makefile

@@ -0,0 +1,15 @@
+.PHONY: test coverage lint vet
+
+build:
+	go build
+goreleaser:
+	goreleaser release --snapshot --rm-dis
+lint:
+	go fmt $(go list ./... | grep -v /vendor/)
+vet:
+	go vet $(go list ./... | grep -v /vendor/)
+test:
+	go test -v -cover ./...
+coverage:
+	go test -v -cover -coverprofile=coverage.out ./... &&\
+	go tool cover -html=coverage.out -o coverage.html

cmd/config.go

@@ -0,0 +1,18 @@
+package cmd
+
+const License = `
+Copyright (C) 2021 NETWAYS GmbH <info@netways.de>
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program. If not, see https://www.gnu.org/licenses/.
+`

main.go

@@ -7,9 +7,10 @@ import (
 
 // nolint: gochecknoglobals
 var (
-	version = "0.1.0"
-	commit  = ""
-	date    = ""
+	// These get filled at build time with the proper vaules
+	version = "development"
+	commit  = "HEAD"
+	date    = "latest"
 )
 
 func main() {
@@ -28,5 +29,7 @@ func buildVersion() string {
 		result = fmt.Sprintf("%s\ndate: %s", result, date)
 	}
 
+	result += "\n" + cmd.License
+
 	return result
 }