updated autotools files (#117).
updated config.guess and config.sub.
supported GtkSpell 2.0.13 (with Enchant).
updated po files, sylpheed.rc.in, and made 2.4.1 release.
fixed a bug of addressbook that multiple selection with Ctrl key didn't work with GTK+ 2.6.9.
added missing includes.
Initial import of Sylpheed (GTK2 version).