Add @since tag to VsyncMode javadoc

graphics/src/main/java/de/staropensource/sosengine/graphics/types/VsyncMode.java

@@ -21,21 +21,29 @@ package de.staropensource.sosengine.graphics.types;
 
 /**
  * Used for determining if and how a window's frame rate should be synchronized to the monitor's refresh rate.
+ *
+ * @since v1-alpha1
  */
 @SuppressWarnings({ "unused" })
 public enum VsyncMode {
     /**
      * Disables VSync. The frame rate can be uncapped and will allow for processing an unlimited amount of frames.
+     *
+     * @since v1-alpha1
      */
     OFF,
 
     /**
      * Enables VSync and will cap the window's frame rate at the refresh rate of the target monitor.
+     *
+     * @since v1-alpha1
      */
     ON,
 
     /**
      * This mode will disables VSync if the window's frame rate drops below the monitor's refresh rate and enable it otherwise.
+     *
+     * @since v1-alpha1
      */
     ADAPTIVE
 }