staticcheck (#313)

* CI: use staticcheck for linting

This commit switches the linter for Go code from golint to staticcheck.
Golint has been deprecated since last year and staticcheck is a
recommended replacement.

Signed-off-by: Lucas Servén Marín <lserven@gmail.com>

* revendor

Signed-off-by: Lucas Servén Marín <lserven@gmail.com>

* cmd,pkg: fix lint warnings

Signed-off-by: Lucas Servén Marín <lserven@gmail.com>

vendor/honnef.co/go/tools/lintcmd/version/buildinfo.go

@@ -0,0 +1,44 @@
+package version
+
+import (
+	"fmt"
+	"runtime/debug"
+)
+
+func printBuildInfo() {
+	if info, ok := debug.ReadBuildInfo(); ok {
+		fmt.Println("Main module:")
+		printModule(&info.Main)
+		fmt.Println("Dependencies:")
+		for _, dep := range info.Deps {
+			printModule(dep)
+		}
+	} else {
+		fmt.Println("Built without Go modules")
+	}
+}
+
+func buildInfoVersion() (string, bool) {
+	info, ok := debug.ReadBuildInfo()
+	if !ok {
+		return "", false
+	}
+	if info.Main.Version == "(devel)" {
+		return "", false
+	}
+	return info.Main.Version, true
+}
+
+func printModule(m *debug.Module) {
+	fmt.Printf("\t%s", m.Path)
+	if m.Version != "(devel)" {
+		fmt.Printf("@%s", m.Version)
+	}
+	if m.Sum != "" {
+		fmt.Printf(" (sum: %s)", m.Sum)
+	}
+	if m.Replace != nil {
+		fmt.Printf(" (replace: %s)", m.Replace.Path)
+	}
+	fmt.Println()
+}