`Check for Updates` button broken after latest cactbot update

[valarnin]

The latest cactbot update included the following commit which switched to using OverlayPlugin's ILogger interface rather than its own.
quisquous/cactbot@d07965a

Normally I'd PR a fix for this issue, but to be honest I have no idea what's going on in the corresponding button handler.

OverlayPlugin/OverlayPlugin.Core/Controls/GeneralConfigTab.cs

Lines 129 to 168 in 1a4232e

	private void btnCactbotUpdate_Click(object sender, EventArgs e)
	{
	try
	{
	var asm = Assembly.Load("CactbotEventSource");
	var checkerType = asm.GetType("Cactbot.VersionChecker");
	var loggerType = asm.GetType("Cactbot.ILogger");
	var configType = asm.GetType("Cactbot.CactbotEventSourceConfig");
	var esList = container.Resolve<Registry>().EventSources;
	IEventSource cactbotEs = null;
	foreach (var es in esList)
	{
	if (es.Name == "Cactbot Config" || es.Name == "Cactbot")
	{
	cactbotEs = es;
	break;
	}
	}
	if (cactbotEs == null)
	{
	MessageBox.Show("Cactbot is loaded but it never registered with OverlayPlugin!", "Error");
	return;
	}
	var cactbotConfig = cactbotEs.GetType().GetProperty("Config").GetValue(cactbotEs);
	configType.GetField("LastUpdateCheck").SetValue(cactbotConfig, DateTime.MinValue);
	var checker = checkerType.GetConstructor(new Type[] { loggerType }).Invoke(new object[] { cactbotEs });
	checkerType.GetMethod("DoUpdateCheck", new Type[] {configType}).Invoke(checker, new object[] { cactbotConfig });
	} catch(FileNotFoundException)
	{
	MessageBox.Show("Could not find Cactbot!", "Error");
	} catch(Exception ex)
	{
	MessageBox.Show("Failed: " + ex.ToString(), "Error");
	}
	}

cc @ngld @quisquous