Add PHP-FPM to php5 role for ansible.

Provides a handler to configure PHP-FPM: install package, keeps the same
configuration of php.ini for FPM and PHP-CLI ans also allows managing
pools.
Move php5 role to root directory.

Providing the structure of a ansible-galaxy package instead of a
repository of many roles. Easing maintenance and allowing third party
developers to also use that role on their development/deploy
environment.

No meta information for ansible-galaxy publication is added, not the
README was updated with usefull information about the package.