Added shell command structure
Added command interface and Calculator job class
Added Symfony Process and prepared Pig command to be called by it
Merge remote-tracking branch 'origin/issue_2'

Conflicts:
	vendor/autoload.php
	vendor/composer/autoload_real.php
	vendor/predis/predis/bin/create-command-test
	vendor/predis/predis/bin/create-pear
	vendor/predis/predis/bin/create-phar
	vendor/predis/predis/bin/create-single-file