Send multiple game-state events (if needed) when a client connects

Send multiple game-state events (if needed) when a client connects

This implements the latest change as of version 0.6 of the API protocol.

This change fixes a bug in the current empires-html client where
reloading the browser when in the middle of the game would break the
client, (by displaying some content that's inappropriate for the
current state). By sending each step-wise transition through the game
states, the client does not get confused.