Add linea theme

configure

configure.in

themes/Makefile.am

themes/Makefile.in

themes/linea/Makefile.am

themes/linea/Makefile.in

themes/linea/bottom-active.xpm

themes/linea/bottom-inactive.xpm

themes/linea/bottom-left-active.xpm

themes/linea/bottom-left-inactive.xpm

themes/linea/bottom-right-active.xpm

themes/linea/bottom-right-inactive.xpm

themes/linea/close-active.xpm

themes/linea/close-inactive.xpm

themes/linea/close-pressed.xpm

themes/linea/hide-active.xpm

themes/linea/hide-inactive.xpm

themes/linea/hide-pressed.xpm

themes/linea/left-active.xpm

themes/linea/left-inactive.xpm