buildroot

irssi: new package

Irssi is a terminal based IRC client for UNIX systems.

http://irssi.org/

[Thomas: use alternate site since the official site is currently
down.]

Signed-off-by: Rodrigo Rebello <rprebello@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>