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
Closes #45
closes #45
Minor change to the prerequisites needed for debian-based hosts
closes #44
Started working on new WN role
Merge pull request #46 from INFN-Catania/master

Iptables management in a separate role
Fixed iptables also for destination nat

Destination nat requested by tomcat.

This require some additional variable. Chech the role dependencies from fmarco76.tomcat
to see what it is needed
Merge pull request #47 from INFN-Catania/master

Fixed iptables also for destination nat
Update README.md
Working on shibboleth role
Merge branch 'master' of https://github.com/AAROC/ansible-for-grid
Update readme
Create init.pp
Create job.pp
Create script.pp
Create job.erb
Create client.pp
Create parser.pp
Create README
Create params.pp