DHT_U doxygen

DHT_U.h

@@ -76,8 +76,16 @@ public:
     int32_t _id;
   };
 
+	/*!
+   *  @brief  Returns temperature stored in _temp
+   *  @return Temperature value
+   */
   Temperature temperature() { return _temp; }
 
+	/*!
+   *  @brief  Returns humidity stored in _humidity
+   *  @return Humidity value
+   */
   Humidity humidity() { return _humidity; }
 
 private: