feat(refacto): move everything in internal package

This allows to install katenary with `go install` and to clean up the
project folder.

internal/generator/labels/labelstructs/cronJob.go

@@ -0,0 +1,18 @@
+package labelstructs
+
+import "gopkg.in/yaml.v3"
+
+type CronJob struct {
+	Image    string `yaml:"image,omitempty" json:"image,omitempty"`
+	Command  string `yaml:"command" json:"command,omitempty"`
+	Schedule string `yaml:"schedule" json:"schedule,omitempty"`
+	Rbac     bool   `yaml:"rbac" json:"rbac,omitempty"`
+}
+
+func CronJobFrom(data string) (*CronJob, error) {
+	var mapping CronJob
+	if err := yaml.Unmarshal([]byte(data), &mapping); err != nil {
+		return nil, err
+	}
+	return &mapping, nil
+}