[PR] Make NTSO only available if a HoS has joined the round

[DimWhat]

To reiterate what I said on the forums. I am mostly for this PR although a small part of me is slightly dissapointed that specific roleplaying situations are slightly more difficult to make happen. I do not think that is a problem though as the roleplaying opportunity is not going away forever or anything. So all in all this PR should go through in my opinion. Having HoS players actually play HoS is a good idea.