Made the classes (ForceRedeem, VoucherReceive, VoucherRedeem) follow the contract provided by Event properly

src/main/java/com/songoda/epicvouchers/events/ForceRedeemEvent.java

@@ -52,4 +52,8 @@ public class ForceRedeemEvent extends Event implements Cancellable {
         return handlers;
     }
 
+    public static HandlerList getHandlerList() {
+        return handlers;
+    }
+
 }

src/main/java/com/songoda/epicvouchers/events/VoucherReceiveEvent.java

@@ -59,4 +59,8 @@ public class VoucherReceiveEvent extends Event implements Cancellable {
         return handlers;
     }
     
+    public static HandlerList getHandlerList() {
+       return handlers;
+    }
+
 }

src/main/java/com/songoda/epicvouchers/events/VoucherRedeemEvent.java

@@ -52,4 +52,8 @@ public class VoucherRedeemEvent extends Event implements Cancellable {
         return handlers;
     }
 
+    public static HandlerList getHandlerList() {
+        return handlers;
+    }
+
 }

src/main/java/com/songoda/epicvouchers/voucher/Voucher.java

@@ -141,7 +141,6 @@ public class Voucher {
     }
 
     public void give(CommandSender sender, List<Player> players, int amount) {
-
         String giveMessage = instance.getLocale().getMessage("command.give.send")
                 .processPlaceholder("player", players.size() == 1 ? players.get(0).getName() : "everyone")
                 .processPlaceholder("voucher", Matcher.quoteReplacement(getName(true)))