- Add a verbose flag and put debugging output being it ("-v" || " --verbose")

- In verbose mode draw a thumbnail of the source image in the bottom left of the window
- Add support for long options in the command line parsing
- Add a "stretch" argument that will stretch the aspect axis to fit the window when set. For example, in landscape mode the drawn picture will be as wide as the window, cropping the top and bottom

src/overlay.h

@@ -27,11 +27,13 @@ class Overlay
     int getMarginBottomRight();
     int getFontsizeBottomRight();
 
+    void setDebugMode(const bool debugMode) { _debugMode = debugMode; }
 
   private:
     const std::string overlayInput;
     int margin;
     int fontsize;
+    bool _debugMode = false;
 
     QString topLeftTemplate;
     QString topRightTemplate;