add more pure virtuals to wxBrushBase; fix the GetColour() functions to return a wxColour object and not a reference; remove from docs the non-existent SetColour(const wxString&) overloads

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@52901 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/gtk1/pen.h

@@ -54,7 +54,7 @@ public:
     void SetDashes( int number_of_dashes, const wxDash *dash );
     void SetStipple(const wxBitmap& stipple);
 
-    wxColour &GetColour() const;
+    wxColour GetColour() const;
     wxPenCap GetCap() const;
     wxPenJoin GetJoin() const;
     wxPenStyle GetStyle() const;