Removing PHP 5.3.3 support

This commit aligns to Zend Framework 2.3's policy on PHP 5.3 support
Adding upgrade notes for the PHP 5.3.23 version requirement bump
PHPCS is only a dev dependency
Bumping ZF2 dependencies, branch alias for master, doctrine-module deps
Adding scrutinizer-ci and phpcs inspections
Lowering requirements until doctrine/DoctrineModule#376 is merged
Adding scrutinizer-ci badges
Lowering required DoctrineModule version to 0.8.x until doctrine/DoctrineModule#376 is merged
Minor CS fixes as of PHPCS
Requiring DoctrineModule 0.9.x since doctrine/DoctrineModule#376 was merged
Merge pull request #306 from doctrine/hotfix/php-5.3.3-drop

Removing PHP 5.3.3 support