NetServer should send hash of previous turns too

[elexis]

This function

bool CNetServerWorker::OnJoinSyncingLoadedGame(void* context, CFsmEvent* event)
{
	// A client rejoining an in-progress game has now finished loading the
	// map and deserialized the initial state.
	// The simulation may have progressed since then, so send any subsequent
	// commands to them and set them as an active player so they can participate
	// in all future turns.

sends the rejoining client past commands.

But it also ought to send the hash values, so that OOS issues can be identified as soon as possible.

(It is nice to be able to derive from the commands.txt when the rejoin finished. But that shouldn't prevent us from fixing this defect IMO.)