Refactor Website

[cdavernas]

What would you like to be added:

Refactor the website, as suggested by @ricardozanini.

Why is this needed:

Adapt to current design goals.
Modernize the UI.

[ricardozanini]

Also add a blog for announcements, tutorials, and so on.

[cdavernas]

@ricardozanini I created #199 to that effect.