feat: run multiple init programs

- We log their outputs and status codes
- Windows is supported as well, leveraging cmd.exe /c

Co-authored-by: pancho horrillo <pancho.horrillo@bbva.com>

test/runwindowsrun.go

@@ -0,0 +1,19 @@
+package main
+
+import (
+	"fmt"
+	"os"
+	"os/exec"
+)
+
+func main() {
+	cmd := exec.Command("rundll32.exe", "url.dll,FileProtocolHandler", os.Args[1])
+	err := cmd.Start()
+	if err != nil {
+		fmt.Println(err)
+	}
+	err = cmd.Wait()
+	if err != nil {
+		fmt.Println(err)
+	}
+}