Replaced phpspec by phpunit
Grunt tests now uses phpunit
Added phpunit config file
phpspec => phpunit for ListCommand
phpspec => phpunit for Version
phpspec => phpunit for HTTPClient
Tests are in the tests\ namespace
phpspec => phpunit for DownloadPage
phpspec => phpunit for ReleasePage
phpspec => phpunit for WebPageFactory
phpspec => phpunit for PHPInstaller
Removed old phpspec files
Merge branch 'feature/change-to-phpunit' into develop