Removes test folder.

Favouring a more explicity directory structure with inventory directory
and the playbook on the root of the project (removing the redundancy of
test/test.yml name).
Create Vagrantfile.

With 4 different boxes (independent VMs) of Debian family to test this
role under.
CentOS 6.5 is added to represent the RedHat family.

Default VM is Ubuntu trusty.
Fix Ubuntu trusty provisioning.

Removes uneeded package from installation list (it is already installed
on system where it is needed) as it doesn't exist on trusty.
Fixes Apache's Virtual host template to properly configure option with
+/- signs prevent warning messages under some
versions/distributions/configurations.

Fixes #2 (GitHub).
CI testing a request is successful.

`curl` on some distributions can return always a successful exit code,
even for 4xx HTTP responses which prompted a change to test the HTTP
status of the response directly.
Fix CentOS/RedHat provisioning.

RedHat uses SELinux, even on permissive, Ansible needs a pyhton package
to do shenanigans with SELinux.
Remove virtual host declaration from defaults.

As the document root varies between OS families, the default needs to be
sensible to that in order so that the `test.yml` playbook works properly
and is testable.