Introducing vibe.d!

[Martin Nowak]

Very nice to see that someone took the async/Fiber idea that far.

Some observations:
- Wouldn't wrapping code in "void main()" instead of "static this()" make  
better front page examples.
- It would be interesting to know what made you write your own Stream/JSON  
implementations.
- I think there is some interest in having the HTTP handling and the  
templates in a separate library.