gui_bootmanager: add a 'sed' based patch method with less dependencies

bootmanager/change_system_reboot_lua.sh

@@ -0,0 +1,20 @@
+#! /bin/sh
+[ -z "$1" ] && printf "Missing name of file as parameter, the file will be changed in place.\n" 1>&2 && exit 1
+! [ -f "$1" ] && printf "File '%s' not found.\n" "$1" 1>&2 && exit 1
+sed -e "
+/^local savecookie/a\\
+if box.post.linux_fs_start then\\
+local linux_fs_start = string.gsub(box.post.linux_fs_start, \"'\", \"\")\\
+local branding = string.gsub(box.post[linux_fs_start..\"_branding\"], \"'\", \"\")\\
+os.execute(\"/usr/bin/gui_bootmanager switch_to '\"..linux_fs_start..\"' '\"..branding..\"'\")\\
+end
+/^<form action/a\\
+<div id=\"managed_reboot\" class=\"reboot_managed\">\\
+<?lua\\
+pipe = io.popen(\"/usr/bin/gui_bootmanager html_display\")\\
+line = pipe:read(\"*a\")\\
+pipe:close()\\
+box.out(line)\\
+?>\\
+</div>
+" -i "$1"