Hi,

I try to create a Slackware container in a Slackware64 14.2 current and
find that wget depends on libunistring.

So I add libunistring to the package list.

Closes #1915

Signed-off-by: Chia-Chun Hsu a12321aabb@gmail.com
Acked-by: Stéphane Graber <stgraber@ubuntu.com>