{gtk-2.0/,}Makefile: update gtk-2.0 specific images
gtk-2.0/img/bg_bevel_in_big.png: added gtk-3.0 notebook image
gtk-2.0/img/day_middle_normal.png: added gtk-3.0 spinbutton image
gtk-3.0/apps/term.css: +vte
gtk-3.0/{gtk{-widgets,}.css: major notebook overhaul/clean up; spinbutton update; button update; toolbar update