COMP: Address VC++ C4251 warnings: needs to have dll-interface to be …

…used by

Since the same compiler is used to compile all components of the project, this
is a non issue.

See https://docs.microsoft.com/en-us/cpp/error-messages/compiler-warnings/compiler-warning-level-1-c4251?view=vs-2019

common/ukf_exports.h

@@ -19,6 +19,14 @@
 #ifndef __UKFExport_h
 #define __UKFExport_h
 
+/** Disable some common warnings in MS VC++ */
+#if defined( _MSC_VER )
+
+// 'identifier' : class 'type' needs to have dll-interface to be used by
+// clients of class 'type2'
+#pragma warning ( disable : 4251 )
+
+#endif
 
 #if defined(WIN32) && !defined(UKF_STATIC)
  #if defined(UKFBase_EXPORTS)