setup.py: add "wget" as a requirement for Fedora

Add "wget" as another requirement for Fedora (we probably need it
for other distros as well), as the vast majority of the modules in
apps/ require it.

Signed-off-by: Nadav Har'El <nyh@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>