Merge pull request #42 from INFN-Catania/master

Install shibboleth
hacking WN role
Merge branch 'master' of https://github.com/AAROC/ansible-for-grid
hacking wn
hacking wn
hacking wn
hacking wn
hacking wn
hacking wn
hacking wn
hacking wn
Iptables management in a separate role

Iptables management extrapolated from the ldap role
and put in a separate role. It is invoked by the role
dependencies option.

Current implementation can take several variable:

ports (this is a range for the destination port), chain and table
(default respectively INPUT and filter).

Nevertheless, the semantic need to be increased in order to cover other situations