update documentation

modules/core/include/opencv2/core.hpp

@@ -202,6 +202,9 @@ enum CovarFlags {
     COVAR_COLS      = 16
 };
 
+//! @addtogroup core_cluster
+//!  @{
+
 //! k-Means flags
 enum KmeansFlags {
     /** Select random initial centers in each attempt.*/
@@ -215,6 +218,8 @@ enum KmeansFlags {
     KMEANS_USE_INITIAL_LABELS = 1
 };
 
+//! @} core_cluster
+
 //! type of line
 enum LineTypes {
     FILLED  = -1,
@@ -236,12 +241,16 @@ enum HersheyFonts {
     FONT_ITALIC                 = 16 //!< flag for italic font
 };
 
+//! @addtogroup core_array
+//! @{
+
 enum ReduceTypes { REDUCE_SUM = 0, //!< the output is the sum of all rows/columns of the matrix.
                    REDUCE_AVG = 1, //!< the output is the mean vector of all rows/columns of the matrix.
                    REDUCE_MAX = 2, //!< the output is the maximum (column/row-wise) of all rows/columns of the matrix.
                    REDUCE_MIN = 3  //!< the output is the minimum (column/row-wise) of all rows/columns of the matrix.
                  };
 
+//! @} core_array
 
 /** @brief Swaps two matrices
 */