Gscope3: Add horizontal and verical grid lines to search-results treeview.
Gscope3: Add horizontal and verical grid lines to search-results treeview.

Improves readability.  GTK-2 style even/odd highlighting patch is out there, but
not included in latest ubuntu gtk3 libs.  Not clear if official GTK maintainers
have picked up the patch.  For now, there are just grid lines.

tefletch/gscope,tefletch/gscope