Add BaseMode::selectNext and PrevSurface methods

src/Application/Modes/ApplicationBaseMode.h

@@ -32,6 +32,10 @@ class ApplicationBaseMode {
 		virtual ofPoint getTranslation(){ return ofPoint(0, 0); }
 		virtual void setTranslation(ofPoint p){}
 	
+		// Undoable public methods
+		virtual void selectNextSurface(Application * app){}
+		virtual void selectPrevSurface(Application * app){}
+
 };
 
 } // namespace piMapper