Bugfix: fix missing child entities (like drybox on rhib) by invalidating network cache on netgroup change Previously if parent moved it would update the network group of the hierarchy, but only parent would have it's cache invalidated. This meant that it was possible for child to be with a netgroup outside of network range, while parent is in network range. Tests: on Craggy, took rhib and drove it from E4 to a row above E0, teleported back to E4, waited for boat to stream out, teleported to boat and waited a bit - it stayed in place (previously drybox would disappear)