Show Nim: Mummy, a new HTTP + WebSocket server that returns to the ancient ways of threads

[guzba]

> Where does the name come from?

Mummy as in <https://m.media-amazon.com/images/I/81MXGwhp0PL._AC_UL1500_.jpg> 
(hence the "ancient ways of threads" line). We'll be adding some kind of little 
graphic to the repo before long here.