Powder keg duplication issue

Hi,
Here is a fix for powder kegs dropping as items just before the explosion and not being destroyed by the explosion, potentially giving players free powder kegs if nothing else destroyed them. I have also removed a duplicate line of code for generating the primed sound.

I do have one issue though, the powder kegs can still be broken (by hand or with other explosions) while primed which means that they still go off but disappear before the explosion. I tried a multitude of things to stop them from being broken but nothing worked quite right so this visual bug (not really very noticeable if you are running away but quite noticeable if you broke the block in a panic to stop it going off) will either need someone else to look at it or for someone to point me in the right direction as to how I can stop a block from being broken by both the player and an explosion. I did try changing the hardness while primed but couldn't do the same with the resistance so dropped those changes.

Another question is, if a player does break the block should the powder keg break and not go off or should the player not be able to break a primed powder keg?