Testing tools

New tools:

• behat - Helps to test business expectations
• infection - AST based PHP Mutation Testing Framework
• phpspec - SpecBDD Framework
• phpunit - The PHP testing framework

Updates:

• phan (0.12.0 => 0.12.2)

Changes:

• Install tagged versions with box and composer install (if available)
• Allow version configuration for box and composer installs
• Add a command to automatically update phar versions php tools.php update-phars

Summary of changes: v1.6.3...v1.7.0