Improving and extending pub coordination environment:

- improved scene descriptions and storyline
- ability to set payoff separately for each iteration
- pubs can be closed, with one of players notified. Tests information spread and communications ability
- choice of using a conversation GM for social scenes for speed and focus

PiperOrigin-RevId: 661232617
Change-Id: If75bb638d7bbc89329bc72f5669b1bb5aff64d46