Adding Markdown to Ddoc

[Bernard Helyer]

On Tuesday, 12 December 2017 at 02:30:39 UTC, Walter Bright wrote:
> It's apparently written in Volt:
>
> https://github.com/VoltLang/Watt
>
> But the two links there to Volt are dead:
>
> https://github.com/VoltLang/Watt/blob/master/volt-lang.org

Ah, the joys of forgetting too ensure URLs in Markdown READMEs 
are absolute.

The correct link is volt-lang.org -- I have fixed that README 
also,
thanks for pointing it out.