Remove redundant setContents() calls from class chest handlers.

Before, these redundant calls didn't really do anything. Now they mess everything up, because setContents() doesn't set inventory contents only, but the entire inventory instead, because that's so super useful. Well done, boys!

#notsalty

src/main/java/com/garbagemule/MobArena/ArenaListener.java

@@ -1103,7 +1103,6 @@ public class ArenaListener
                                 contents = newContents;
                             }
                             arena.assignClassGiveInv(p, className, contents);
-                            p.getInventory().setContents(contents);
                             Messenger.tell(p, Msg.LOBBY_CLASS_PICKED, TextUtils.camelCase(className));
                             if (price > 0D) {
                                 Messenger.tell(p, Msg.LOBBY_CLASS_PRICE,  plugin.economyFormat(price));

src/main/java/com/garbagemule/MobArena/commands/user/PickClassCommand.java

@@ -101,7 +101,6 @@ public class PickClassCommand implements Command
                         contents = newContents;
                     }
                     arena.assignClassGiveInv(p, lowercase, contents);
-                    p.getInventory().setContents(contents);
                     Messenger.tell(p, Msg.LOBBY_CLASS_PICKED, TextUtils.camelCase(lowercase));
                     if (price > 0D) {
                         Messenger.tell(p, Msg.LOBBY_CLASS_PRICE, am.getPlugin().economyFormat(price));