Fix always to end of line jumping cursor in MakeStepConfigWidget

Also rename some methods/signal to make clearer that those only are
relevevant for user changes not for all arguments.

src/plugins/qt4projectmanager/qmakestep.cpp

@@ -327,6 +327,8 @@ void QMakeStepConfigWidget::userArgumentsChanged()
         return;
     QString qmakeArgs = ProjectExplorer::Environment::joinArgumentList(m_step->userArguments());
     m_ui.qmakeAdditonalArgumentsLineEdit->setText(qmakeArgs);
+    updateTitleLabel();
+    updateEffectiveQMakeCall();
 }
 
 void QMakeStepConfigWidget::init()