make firejet look cool, also missed null check in surge wall

src/com/projectkorra/projectkorra/PKListener.java

@@ -1659,6 +1659,10 @@ public class PKListener implements Listener {
 				return;
 			}
 		}
+
+		if (CoreAbility.getAbility(player, FireJet.class) != null) {
+			event.setCancelled(true);
+		}
 	}
 
 	@EventHandler(priority = EventPriority.HIGHEST, ignoreCancelled = true)

src/com/projectkorra/projectkorra/firebending/FireJet.java

@@ -79,6 +79,7 @@ public class FireJet extends FireAbility {
 			this.time = System.currentTimeMillis();
 
 			this.start();
+			player.setGliding(true);
 			this.bPlayer.addCooldown(this);
 		}
 	}
@@ -116,6 +117,7 @@ public class FireJet extends FireAbility {
 	public void remove() {
 		super.remove();
 		flightHandler.removeInstance(this.player, this.getName());
+		player.setGliding(false);
 	}
 
 	@Override

src/com/projectkorra/projectkorra/waterbending/SurgeWall.java

@@ -380,7 +380,9 @@ public class SurgeWall extends WaterAbility {
 			if (WALL_BLOCKS.containsKey(block)) {
 				if (this.oldTemps.containsKey(block)) {
 					final TempBlock tb = TempBlock.get(block);
-					tb.setType(this.oldTemps.get(block));
+					if (tb != null) {
+						tb.setType(this.oldTemps.get(block));
+					}
 				} else {
 					TempBlock.revertBlock(block, Material.AIR);
 				}