add some constants string to constants

src/Bundle/ChillPersonBundle/Entity/AccompanyingPeriod.php

@@ -42,7 +42,37 @@ use Chill\MainBundle\Entity\User;
  */
 class AccompanyingPeriod
 {
-    const INTENSITY = ['occasional', 'regular'];
+    /**
+     * Mark an accompanying period as "occasional"
+     * 
+     * used in INTENSITY
+     */
+    public const INTENSITY_OCCASIONAL = 'occasional';
+    
+    /**
+     * Mark an accompanying period as "regular"
+     * 
+     * used in INTENSITY
+     */
+    public const INTENSITY_REGULAR = 'regular';
+    
+    public const INTENSITIES = [self::INTENSITY_OCCASIONAL, self::INTENSITY_REGULAR];
+    
+    /**
+     * Mark an accompanying period as "draft".
+     * 
+     * This means that the accompanying period is not yet 
+     * confirmed by the creator
+     */
+    public const STEP_DRAFT = 'DRAFT';
+    
+    /**
+     * Mark an accompanying period as "confirmed".
+     * 
+     * This means that the accompanying period **is** 
+     * confirmed by the creator
+     */
+    public const STEP_CONFIRMED = 'CONFIRMED';
     
     /**
      * @var integer
@@ -117,7 +147,7 @@ class AccompanyingPeriod
      * @var string
      * @ORM\Column(type="string", length=32, nullable=true)
      */
-    private $step = 'DRAFT';
+    private $step = self::STEP_DRAFT;
     
     /**
      * @ORM\ManyToOne(targetEntity=Origin::class)