Highlight both matching brackets, fixes #559128
Highlight both matching brackets, fixes #559128

Patch provided by: Andy Owen

cburschka/gtksourceview,cburschka/gtksourceview,uajain/gtksourceview,GNOME/gtksourceview,cburschka/gtksourceview,GNOME/gtksourceview,uajain/gtksourceview,GNOME/gtksourceview,cburschka/gtksourceview,cburschka/gtksourceview,cburschka/gtksourceview,uajain/gtksourceview,GNOME/gtksourceview,GNOME/gtksourceview,GNOME/gtksourceview,GNOME/gtksourceview,cburschka/gtksourceview,GNOME/gtksourceview,uajain/gtksourceview,GNOME/gtksourceview,GNOME/gtksourceview,GNOME/gtksourceview,uajain/gtksourceview,uajain/gtksourceview,cburschka/gtksourceview,uajain/gtksourceview,GNOME/gtksourceview,cburschka/gtksourceview,uajain/gtksourceview,uajain/gtksourceview,GNOME/gtksourceview,cburschka/gtksourceview,uajain/gtksourceview,GNOME/gtksourceview,GNOME/gtksourceview