Fix headless horseman

Adds buy permission
Actually mounts the player
Disallows broken versions
Removes entity on disconnect/dismount

Commons/core/src/main/i18n/templates/lobby/LobbyMessages.properties

@@ -57,4 +57,6 @@ trial.joinFull = join full servers
 trial.chooseTeam = choose their team
 
 # {0} = shop URL
-trial.upgrade = Visit {0} to extend your membership.
+trial.upgrade = Visit {0} to extend your membership.
+
+version.too.old.gizmo = This gizmo requires at least Minecraft 1.9

Lobby/src/main/java/tc/oc/lobby/bukkit/gizmos/halloween/horse/HeadlessHorsemanGizmo.java

@@ -35,6 +35,11 @@ public class HeadlessHorsemanGizmo extends HalloweenGizmo implements Listener {
         Bukkit.getPluginManager().registerEvents(this, Lobby.get());
     }
 
+    @Override
+    public boolean canPurchase(Player player) {
+        return player.hasPermission("lobby.gizmo.buy.horse") || player.isOp();
+    }
+
     @EventHandler(ignoreCancelled = true)
     public void onPlayerInteract(PlayerInteractEvent e) {
         if(!(Gizmos.gizmoMap.get(e.getPlayer()) instanceof HeadlessHorsemanGizmo)