Extract sdk into its own lib

This had some side effects:

 - Have to add some utils from the kairos/machine modules, which IMHO
   should not be there, they should be here if the are generic enough
 - Dropping the sdk dir, just have the modules in the root dir

Signed-off-by: Itxaka <itxaka.garcia@spectrocloud.com>

utils/utils.go

@@ -0,0 +1,64 @@
+package utils
+
+import (
+	"fmt"
+	"github.com/denisbrodbeck/machineid"
+	"github.com/joho/godotenv"
+	"os"
+	"os/exec"
+)
+
+func SH(c string) (string, error) {
+	cmd := exec.Command("/bin/sh", "-c", c)
+	cmd.Env = os.Environ()
+	o, err := cmd.CombinedOutput()
+	return string(o), err
+}
+
+func SHInDir(c, dir string) (string, error) {
+	cmd := exec.Command("/bin/sh", "-c", c)
+	cmd.Env = os.Environ()
+	cmd.Dir = dir
+	o, err := cmd.CombinedOutput()
+	return string(o), err
+}
+
+func Exists(path string) bool {
+	_, err := os.Stat(path)
+
+	return !os.IsNotExist(err)
+}
+
+// UUID TODO: move this into a machine submodule
+func UUID() string {
+	if os.Getenv("UUID") != "" {
+		return os.Getenv("UUID")
+	}
+	id, _ := machineid.ID()
+	hostname, _ := os.Hostname()
+	return fmt.Sprintf("%s-%s", id, hostname)
+}
+
+func OSRelease(key string) (string, error) {
+	release, err := godotenv.Read("/etc/os-release")
+	if err != nil {
+		return "", err
+	}
+	v, exists := release[key]
+	if !exists {
+		return "", fmt.Errorf("key not found")
+	}
+	return v, nil
+}
+
+func FindCommand(def string, options []string) string {
+	for _, p := range options {
+		path, err := exec.LookPath(p)
+		if err == nil {
+			return path
+		}
+	}
+
+	// Otherwise return default
+	return def
+}