Added 4 crates, restructured Jungle props folder, created prefabs for both barrels and crates, fixed exploding barrel

Added 4 crates, restructured Jungle props folder, created prefabs for both barrels and crates, fixed exploding barrel, removed enemies and put them back to fix bullet collision issues.  Colliders had some type of errors in them.  Enemies didn't need to be aimed at in order to hit.  Fixed this by deleting and adding directly from the prefab folder.