Issue 1346: flatfield shortcut to current dir; relative paths in .pp3 if referring to files in same dir or subdir

rtgui/toolpanelcoord.cc

@@ -362,6 +362,7 @@ void ToolPanelCoordinator::initImage (rtengine::StagedImageProcessor* ipc_, bool
         ipc->setSizeListener (crop);
         ipc->setSizeListener (resize);
     }
+    flatfield->setShortcutPath(Glib::path_get_dirname(ipc->getInitialImage()->getFileName()));
 
     icm->setRawMeta (raw, (const rtengine::ImageData*)pMetaData); 
     lensProf->setRawMeta (raw, pMetaData); 
@@ -630,3 +631,8 @@ void ToolPanelCoordinator::toolSelected (ToolMode tool) {
 		break;
 	}
 }
+
+void ToolPanelCoordinator::dirSelected (const Glib::ustring& dirname, const Glib::ustring& openfile) {
+
+    flatfield->setShortcutPath(dirname);
+}