Main window: implement the logging options dialog. Use it only for log level

logging/logger.h

@@ -92,6 +92,13 @@ public:
     */
     void installMsgHandler();
 
+    /**
+     * Sets the minimum message level on the fly
+     */
+    void setMinMessageLevel(const QtMsgType& minMsgLevel) {
+        minLevel = minMsgLevel;
+    }
+
     /**
       Sets a thread-local variable that may be used to decorate log messages.
       This method is thread safe.