Update doxygen comments

lib/Navigation/navigation.h

@@ -128,14 +128,8 @@ class Navigation {
          */
         bool addCurrentPosToRoute();
 
-        bool setPointBeforeTurn();
-
-        // /**
-        //  * @brief Returns the GPS object
-        //  * 
-        //  * @return SFE_UBLOX_GNSS* 
-        //  */
-        // SFE_UBLOX_GNSS* getGPS() { return this->gps; }
+    	// TODO: can be deleted?
+        // bool setPointBeforeTurn();
         
         /**
          * @brief Get the Ubx Data object
@@ -163,8 +157,25 @@ class Navigation {
          */
         RouteInfo getRouteInfo() const { return this->route->getRouteInfo(); }
         Route* getRoute() const { return this->route; }
+
+        /**
+         * @brief Get azimuth
+         * 
+         * This value represents the angle between north and 
+         * the line of sight. Clockwise.
+         * 
+         * @return uint16_t degree
+         */
         uint16_t getAzimuth() const { return this->azimuth; }
 
+        /**
+         * @brief Set the output status for PVTdata.
+         * 
+         * If this is true, a lot of information from the gnss module will be printed in
+         * the interval of navigation frequency.
+         * 
+         * @param status 
+         */
         static void setOutputStatusPrintPVTdata(bool status);
 
     private: