Better logger

1. Throw exception for fatal/error log when debugging
2. Write to debug output for warn/debug/info log when debugging
3. part of #355

Wox.Test/Plugins/PluginInitTest.cs

@@ -11,7 +11,7 @@ namespace Wox.Test.Plugins
         [Test]
         public void PublicAPIIsNullTest()
         {
-            Assert.Throws(typeof(WoxCritialException), () => PluginManager.Init(null));
+            Assert.Throws(typeof(WoxFatalException), () => PluginManager.Init(null));
         }
     }
 }