standalone URL-safe base64-compatible codec for Erlang

 Base64Url is a standalone, URL-safe and base64-compatible codec for Erlang.
 It supports URL-safe base64 en- and decoding. Some systems in the wild use
 base64 URL encoding, but keep the padding for MIME compatibility
 (base64 Content-Transfer-Encoding).
 Base64Url allows one to interact with such systems.