A simple patch to enable the users to press "Escape Key" to navigate back one level while viewing pictures in the slideshow in the ImageViewer of Plasma Media Center. 
Earlier, while viewing pictures, user did not had any option to go back one level while viewing pictures in the slideshow. The only option was to mouse click the back button which took us back to the "Welcome" screen of the PMC.
Now, one can press Escape to come back to the folder in which the photos were being viewed !

Testing Done: works as intended