I have easily ported the Encode64 from JS to c# ; Also, for simple use cases e.g "Alice -> Bob Hello", the `System.IO.Compression.DeflateStream` from c# produces an URL that
http://plantuml.com/image/encodedText... understands, however anything more complex the planuml.com returns an error.
How can I create the equivalent of somewhat proprietary Javascript Encode64(zip_deflate(s,9)) of Plantuml in c# code?