No interaction in installation

Related to #601

Now installation can be done totally automatically specifying the following parameters:

 * ```--url```: PHPCI Installation URL
 * ```--db-host```:  Database hostname
 * ```--db-name```:  Database name
 * ```--db-user```:  Database username
 * ```--db-pass```:  Database password
 * ```--admin-name```:  Admin username
 * ```--admin-pass```:  Admin password
 * ```--admin-mail```: Admin e-mail