Vibe.d tutorial

[Rey Valeza via Digitalmars-d-learn]

Hi, I wrote a tutorial on Vibe.d while trying to re-learn Vibe.d. 
I find that most of Kai Nacke's book need updating, so I wrote a 
tutorial while trying to re-learn it.

Here it is.
https://github.com/reyvaleza/vibed/commit/27ec3678f25d1dd414fae1390677397a7bc57721

I would be glad if you can give me some feedback so I can improve 
it.

Thanks!