Added the file encryption/decryption to Zend\Crypt

This PR replace the https://github.com/zendframework/zf2/pull/6410 with a new `FileCipher` implementation based on the suggestion of #6410. I removed the fluent interface and other methods not really relevant for the usage of this component. I also improved the unit tests adding the one for `Zend\Crypt\Symmetric\Padding\NoPadding`.