Switch mcrypt to openssl

Fixed Rijndael256 bug

Merge pull request ambta#17 from michaelfeinbier/cli-performance

CLI performance on batch encryption

Merge pull request ambta#9 from jongotlin/patch-1

Improved readability

Changed requirements

Merge branch 'master' of https://github.com/ambta/DoctrineEncryptBundle

Merge pull request ambta#2 from wassafr/master

Ignored MappedSuperclass

Merge branch 'master' of https://github.com/ambta/DoctrineEncryptBundle

Merge branch 'master' of https://github.com/ambta/DoctrineEncryptBundle