v0.2.55..v0.2.56 changeset KeepTagsVisitor.h

diff --git a/hoot-core/src/main/cpp/hoot/core/visitors/KeepTagsVisitor.h b/hoot-core/src/main/cpp/hoot/core/visitors/KeepTagsVisitor.h
index efab473..b593009 100644
--- a/hoot-core/src/main/cpp/hoot/core/visitors/KeepTagsVisitor.h
+++ b/hoot-core/src/main/cpp/hoot/core/visitors/KeepTagsVisitor.h
@@ -42,8 +42,9 @@ public:
 
   static std::string className() { return "hoot::KeepTagsVisitor"; }
 
-  KeepTagsVisitor();
+  KeepTagsVisitor() = default;
   explicit KeepTagsVisitor(const QStringList& keys);
+  virtual ~KeepTagsVisitor() = default;
 
   virtual void visit(const std::shared_ptr<Element>& e);