Develop (#3)

* Update command added
* Ensure that the upgraded version is really greater
* Update command should not update prerelease
* Minor presentation changes
* Fix command generation in containers from docker-compose file
- Refactored service creation
* Place the full command to the "cmd" package
* Update cobra to v1.4.0
* Updated build and release creation
* Created an install script
* Add more doc
* Add some tests...
* Add a test directive in Makefile

update/update_test.go

@@ -0,0 +1,52 @@
+package update
+
+import (
+	"fmt"
+	"os"
+	"testing"
+)
+
+func TestDownloadLatestRelease(t *testing.T) {
+
+	// Reset the version to test the latest release
+	Version = "0.0.0"
+
+	// change "exe" to /tmp/test-katenary
+	exe = "/tmp/test-katenary"
+	defer os.Remove(exe)
+
+	// Now call the CheckLatestVersion function
+	version, assets, err := CheckLatestVersion()
+
+	if err != nil {
+		t.Errorf("Error: %s", err)
+	}
+
+	fmt.Println("Version found", version)
+
+	// Touch exe binary
+	f, _ := os.OpenFile(exe, os.O_RDONLY|os.O_CREATE, 0755)
+	f.Write(nil)
+	f.Close()
+
+	err = DownloadLatestVersion(assets)
+	if err != nil {
+		t.Errorf("Error: %s", err)
+	}
+}
+
+func TestAlreadyUpToDate(t *testing.T) {
+	Version = "99999.999.99"
+	exe = "/tmp/test-katenary"
+	defer os.Remove(exe)
+
+	// Call the version check
+	version, _, err := CheckLatestVersion()
+
+	if err == nil {
+		t.Errorf("Error: %s", err)
+	}
+
+	t.Log("Version is already the most recent", version)
+
+}