Added new __WXMOTIF20__ macro, which is true if the Motif version

is 2.0 or higher.
  Now Motif 2.0 or better (but not Lesstif) uses XmRenderTable instead
of the deprecated XmFontList. This allows underlined text in controls.
  Miscellaneous cleanup; used wxXmString in some more places.


git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@19495 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/motif/private.h

@@ -109,7 +109,10 @@ public:
         m_string = XmStringCreateLtoR((char *)str.c_str(),
             XmSTRING_DEFAULT_CHARSET);
     }
-    
+
+    // just to avoid calling XmStringFree()
+    wxXmString(const XmString& string) { m_string = string; }
+
     ~wxXmString() { XmStringFree(m_string); }
     
     // semi-implicit conversion to XmString (shouldn't rely on implicit