Update Virtualbox image to ubuntu/trusty64 with PHP 5.5

[benlk]

precise64 is almost 4 years old, and doesn't receive the 5.3.29 update of the PHP 5.3 it uses. It doesn't install PHP 5.5, which is what is used by WP Engine.

• change Vagrantfile
• check packages that are installed by https://github.com/INN/deploy-tools/blob/41-trusty64/vagrant/boot-script.sh
• figure out which overlays aren't being positioned correctly
• reposition overlays and/or update them to work with new package versions

[benlk]

Newest versions of PHPunit require PHP 5.6. WPEngine uses 5.5.9, according to http://phpinfo.wpengine.com/

• Deploy-tools for PHP version 5.3 should use an older version of PHPunit in the bootstrap script:

  deploy-tools/vagrant/boot-script.sh

  Lines 119 to 122 in 15b722a

  	# Install PHPUnit for wp unit testing.
  	wget https://phar.phpunit.de/phpunit.phar
  	chmod +x phpunit.phar
  	mv phpunit.phar /usr/local/bin/phpunit

[benlk]

Branch with work for this is https://github.com/INN/deploy-tools/tree/41-trusty64

[benlk]

I'm going to close this, since we appear to be going with the VVV option of #48.