2.5

Render usability:

- Option back to render to imagewindow, or fullscreen.
  The latter is default. Setting is stored in Scene.
- Added button in output panel, the option "to new window" will follow!
- F11 again toggles render view
  (moved MS Windows "full screen" to shift+F11 for now)

source/blender/blenkernel/intern/image.c

@@ -253,6 +253,10 @@ void free_image(Image *ima)
 	if (ima->preview) {
 		BKE_previewimg_free(&ima->preview);
 	}
+	if (ima->render_text) {
+		MEM_freeN(ima->render_text);
+		ima->render_text= NULL;
+	}
 }
 
 /* only image block itself */