added CreateByName(), use it in wxColourDatabase

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@24212 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/gtk1/colour.h

@@ -80,6 +80,9 @@ public:
     unsigned char Blue() const;
 
 
+    // Get colour from name or wxNullColour
+    static wxColour CreateByName(const wxString& name);
+
     // Implementation part
     void CalcPixel( GdkColormap *cmap );
     int GetPixel() const;