Move CompletionModel to a more appropriate folder

src/channel.hpp

@@ -3,7 +3,7 @@
 #include "messages/image.hpp"
 #include "messages/limitedqueue.hpp"
 #include "messages/message.hpp"
-#include "singletons/helper/completionmodel.hpp"
+#include "util/completionmodel.hpp"
 #include "util/concurrentmap.hpp"
 
 #include <QMap>
@@ -65,7 +65,7 @@ public:
 
     static std::shared_ptr<Channel> getEmpty();
 
-    singletons::CompletionModel completionModel;
+    CompletionModel completionModel;
 
 protected:
     virtual void onConnected();