Patching more NPEs involving invbalid players, plus mob health bars.

src/main/java/com/gmail/nossr50/listeners/PlayerListener.java

@@ -427,6 +427,10 @@ public class PlayerListener implements Listener {
         ItemStack heldItem = player.getItemInHand();
         McMMOPlayer mcMMOPlayer = UserManager.getPlayer(player);
 
+        if (mcMMOPlayer == null) {
+            return;
+        }
+
         switch (event.getAction()) {
             case RIGHT_CLICK_BLOCK:
                 Block block = event.getClickedBlock();

src/main/java/com/gmail/nossr50/util/MobHealthbarUtils.java

@@ -46,7 +46,10 @@ public final class MobHealthbarUtils {
 
         PlayerProfile profile = UserManager.getPlayer(player).getProfile();
 
-        if (profile.getMobHealthbarType() == MobHealthbarType.DISABLED) {
+        if (profile == null) {
+            return;
+        }
+        else if (profile.getMobHealthbarType() == MobHealthbarType.DISABLED) {
             return;
         }