Adds PHP-CS-Fixer as dev dependency

https://github.com/fabpot/PHP-CS-Fixer
[travis] Update script for get php-cs-fixer from Composer install
Merge pull request #5285 in master
Merge pull request #5284 from samsonasik/add.zendcache.atmemory

added zendframework/zend-cache as suggest dependency at Zend\Memory
Merge branch 'hotfix/php-cs-fixer' of github.com:Maks3w/zf2 into Maks3w-hotfix/php-cs-fixer
Forward port #5281