NeosCMS EEL helper to encode strings to base64

TL;DR

1. Install the package: composer require onedrop/base64

Encode

prop = 'Bier'
prop.@process.encode = ${Onedrop.Base64.encode(value)} // Qmllcg==

Decode

prop = 'Qmllcg=='
prop.@process.decode = ${Onedrop.Base64.decode(value)} // Bier