ADD: added isValid() func to Data template

include/SimCore/data.hpp

@@ -34,11 +34,17 @@ namespace SimCore
                 return data_;
             }
 
+            [[deprecated("isValid() instead")]]
             bool getValidity()
             {
                 return valid_;
             }
 
+            bool isValid()
+            {
+                return valid_;
+            }
+
             std::uint64_t getWriteTime()
             {
                 return writeTime_;