script: move Script into config package

config/script.go

@@ -0,0 +1,16 @@
+package config
+
+import (
+	"strings"
+)
+
+type Script []byte
+
+func IsScript(userdata string) bool {
+	header := strings.SplitN(userdata, "\n", 2)[0]
+	return strings.HasPrefix(header, "#!")
+}
+
+func NewScript(userdata string) (Script, error) {
+	return Script(userdata), nil
+}