Revamp homepage

[WebFreak001]

feedback from the forums:

On the very first page, there are links to the DUB registry website and assorted man pages. You've just lost half the audience right there. The best possible outcome is that the user is confused but pushes on. It says "You can also skip ahead to First steps if you already have dub installed." How do they know if it's installed?

The first page has to be crystal clear. It can't have distractions or require knowledge of the installation status of this thing called "DUB".

The "First Steps" page is likely to be the last steps for many. It provides a CLI command and then shows a bunch of output from an interactive session with no explanation. That's followed by a brief discussion of directories and files. There's also mention of .gitignore, so I guess that means Git is required to use DUB. Then there's discussion of two formats, with no information on how to choose, or why it's important. That's followed by a presentation of configuration files with no explanation.

[renatoathaydes]

I hope that my PR addresses some of the complaints (which I have to agree with). The person who wrote that probably spent more effort doing that than I did creating this PR.