ZKL: Add UnitSync dialog box. Is OFF by default. It allow ZKL to read new map/mod file without being connected to server & allow user to choose not to register new map/mod with server.
Some improvement to UnitSync dialog box:
1) add tooltip
2) add timeout timer (30 second) to avoid AFK-er blocking SpringScanner for infinitely long time.
3) some tweak to Option description (Config.cs)
MinimapFuncBox & ContextMenus : show Spring AI option (in AddAI button) for BA and other mod that don't have LUAAI

SpringsettingForm: ops, fix previous commit of this file didn't work (forgot to actually set the SpringPath).
SpringScanner: use Invoke as suggested by Licho

(for multiple thread safety!)
SpringScanner: use Invoke instead of DynamicInvoke

(got reassurance from Licho this is the one to use)
Merge pull request #234 from xponen/zkl_unitsyncDialogBox

ZKL: Add UnitSync dialog box.