fix: abort and fail logic in tasks

Also sets up correctly the status connections

launcher/tasks/Task.cpp

@@ -100,6 +100,7 @@ void Task::emitAborted()
     m_failReason = "Aborted.";
     qDebug() << "Task" << describe() << "aborted.";
     emit aborted();
+    emit finished();
 }
 
 void Task::emitSucceeded()

launcher/tasks/Task.h

@@ -79,7 +79,7 @@ class Task : public QObject {
 
    public slots:
     virtual void start();
-    virtual bool abort() { return false; };
+    virtual bool abort() { if(canAbort()) emitAborted(); return canAbort(); };
 
    protected:
     virtual void executeTask() = 0;