expose hologram refresh delay in api

api/src/main/java/lol/pyr/znpcsplus/api/hologram/Hologram.java

@@ -41,4 +41,16 @@ public interface Hologram {
      * @return The number of lines in the hologram
      */
     int lineCount();
+
+    /**
+     * Gets the refresh delay of the hologram
+     * @return The refresh delay of the hologram
+     */
+    long getRefreshDelay();
+
+    /**
+     * Sets the refresh delay of the hologram
+     * @param delay The delay to set
+     */
+    void setRefreshDelay(long delay);
 }

plugin/src/main/java/lol/pyr/znpcsplus/hologram/HologramImpl.java

@@ -147,10 +147,12 @@ public class HologramImpl extends Viewable implements Hologram {
         for (HologramLine<?> line : lines) line.hide(player);
     }
 
+    @Override
     public long getRefreshDelay() {
         return refreshDelay;
     }
 
+    @Override
     public void setRefreshDelay(long refreshDelay) {
         this.refreshDelay = refreshDelay;
     }