Add wxDir::Close().

This is trivial to have and can sometimes be useful and also is symmetric to
Open().

Closes #14493.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@72204 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/dir.h

@@ -94,12 +94,15 @@ public:
     // opens the directory for enumeration, use IsOpened() to test success
     wxDir(const wxString& dir);
 
-    // dtor cleans up the associated resources
-    ~wxDir();
+    // dtor calls Close() automatically
+    ~wxDir() { Close(); }
 
     // open the directory for enumerating
     bool Open(const wxString& dir);
 
+    // close the directory, Open() can be called again later
+    void Close();
+
     // returns true if the directory was successfully opened
     bool IsOpened() const;