BattleChatControl.cs: Fix user accidentally change ally when clicking pl...

...ayername or botname in player list box (appropriate way is to click on alliance title).

Other change:
PlayerListBox.cs: Add safety check against out-of-bound error. The error might happen when player list box is changed rapidly (such rapidity is done by Skirmisher tab)

BattleBar.cs: Tiny optimization. Only process "side" (faction) comboBox when its visible.