BattlePlayerList.cs: ops, fix "Hide Passworded" button didn't show saved config
use ActionHandler.ClosePrivateChat() as suggested in https://github.com/ZeroK-RTS/Zero-K-Infrastructure/pull/172
Merge pull request #195 from xponen/ui_tweak_prev_PR

ZKL: ops, fix "Hide passworded" checkbox didn't load saved value from config