logic: initially parse source on message thread and add more StatusBar messages

This change puts the initial project loading into a MessageLoadProject so that the UI thread is still responding.
Also the StatusBar is now responding to more Messages and it's MessageListeners get added to the MessageQueue in
front of other listeners so that the StatusBar UI can announce actions.

src/test/MessageQueueTestSuite.h

@@ -107,6 +107,28 @@ public:
 		}
 	}
 
+	void test_listener_registration_to_front_and_back_within_message_handling(void)
+	{
+		MessageQueue::getInstance()->startMessageLoopThreaded();
+
+		Test5MessageListener listener;
+
+		TestMessage().dispatch();
+		TestMessage().dispatch();
+		TestMessage().dispatch();
+
+		waitForThread();
+
+		MessageQueue::getInstance()->stopMessageLoop();
+
+		TS_ASSERT_EQUALS(5, listener.m_listeners.size());
+		TS_ASSERT_EQUALS(2, listener.m_listeners[0]->m_messageCount);
+		TS_ASSERT_EQUALS(2, listener.m_listeners[1]->m_messageCount);
+		TS_ASSERT_EQUALS(2, listener.m_listeners[2]->m_messageCount);
+		TS_ASSERT_EQUALS(2, listener.m_listeners[3]->m_messageCount);
+		TS_ASSERT_EQUALS(2, listener.m_listeners[4]->m_messageCount);
+	}
+
 private:
 	class TestMessage: public Message<TestMessage>
 	{
@@ -129,8 +151,9 @@ private:
 	class TestMessageListener: public MessageListener<TestMessage>
 	{
 	public:
-		TestMessageListener()
-			: m_messageCount(0)
+		TestMessageListener(bool toFront = false)
+			: MessageListener<TestMessage>(toFront)
+			, m_messageCount(0)
 		{
 		}
 
@@ -195,6 +218,25 @@ private:
 		}
 	};
 
+	class Test5MessageListener:
+		public MessageListener<TestMessage>
+	{
+	public:
+		std::vector<std::shared_ptr<TestMessageListener>> m_listeners;
+
+	private:
+		virtual void handleMessage(TestMessage* message)
+		{
+			if (!m_listeners.size())
+			{
+				for (size_t i = 0; i < 5; i++)
+				{
+					m_listeners.push_back(std::make_shared<TestMessageListener>(i % 2 == 1));
+				}
+			}
+		}
+	};
+
 	void waitForThread() const
 	{
 		static const int THREAD_WAIT_TIME_MS = 5;