Fix default repository

# Regular repositories
deb http://http.kali.org/kali sana main non-free contrib
deb http://security.kali.org/kali-security sana/updates main contrib non-free
# Source repositories
deb-src http://http.kali.org/kali sana main non-free contrib
deb-src http://security.kali.org/kali-security sana/updates main contrib non-free