Fix API classes toString() implementations

plugin/src/main/java/me/filoghost/holographicdisplays/plugin/api/current/DefaultVisibilitySettings.java

@@ -86,7 +86,7 @@ public class DefaultVisibilitySettings implements VisibilitySettings {
 
     @Override
     public String toString() {
-        return "DefaultVisibilitySettings{"
+        return "VisibilitySettings{"
                 + "defaultVisibility=" + defaultVisibility
                 + ", visibilityByPlayer=" + visibilityByPlayer
                 + "}";

plugin/src/main/java/me/filoghost/holographicdisplays/plugin/api/current/SimpleHologramLineClickEvent.java

@@ -21,4 +21,11 @@ class SimpleHologramLineClickEvent implements HologramLineClickEvent {
         return player;
     }
 
+    @Override
+    public String toString() {
+        return "HologramLineClickEvent{"
+                + "player=" + player
+                + "}";
+    }
+
 }

plugin/src/main/java/me/filoghost/holographicdisplays/plugin/api/current/SimpleHologramLinePickupEvent.java

@@ -21,4 +21,11 @@ class SimpleHologramLinePickupEvent implements HologramLinePickupEvent {
         return player;
     }
 
+    @Override
+    public String toString() {
+        return "HologramLinePickupEvent{"
+                + "player=" + player
+                + "}";
+    }
+
 }