Updated README.

Added requirements, usage, dev requirements, license info and contributing steps.
Merge pull request #1 from razielgn/patch-1

Updated README.
Basic Vagrantfile with ansible config.
Added base role, with utils & such.
Added basic MariaDB role.
Added basic Apache2 role.
Added Git role.
Added php5 role.
Enabled mod-rewrite in apache2 role.
Added mailcatcher role.
Added composer role.
Added drush role.
Added phing role.
Added selenium-server role.
Added PhantomJS role.
Added Agavee custom vhosts role.
Vastly improved README.