Update README to clarify virtual host docroots

With the previous wording I got confused and expected Vagrant to create the
docroot directory for me. This wording will help clarify this for future users.
Merge pull request #66 from captbaritone/docroot-readme-update

Confusing wording in the README regarding docroot
Update php-box cookbook, close #70
Merge branch 'develop'
Refactor wp-cli installer, close #71
Merge branch 'develop'
Update Mailcatcher info in README, close #65
Merge pull request #72 from r8/develop

Update Mailcatcher info in README, close #65