Adds documentation to the implemented modules.

sbf-cpp/Genders.h

@@ -34,8 +34,15 @@ namespace SBF {
         kGenderTransFemaleLabel,
         kGenderNonBinaryLabel,
     };
-    std::string GetGenderLabel(int genderId);
-    void FillGenderLabels(std::vector<std::string>& genderLabels);
+    
+    /// @brief Gets a gender label with a specific id.
+    /// @param gender_id The id of the gender to return the label for.
+    /// @return The label of the specified gender or an empty string if gender_id is invalid.
+    std::string GetGenderLabel(int gender_id);
+
+    /// @brief Fills the provided vector with all of the valid gender labels.
+    /// @param gender_labels The vector to fill. It will be cleared first.
+    void FillGenderLabels(std::vector<std::string>& gender_labels);
 } // End namespace SBF
 /** @}*/
 #endif // End !defined GENDERS_H__