Reorganize the Site [WIP]

For the most part, the website should support the channel. So I moved things around to make the hierarchy a bit flatter and easier to navigate.

* The "Rules" section is the must-read section for using the channel. This is stuff that we either will ban or formally warn people for.
* The "Using #CSS" section is helpful advice for using the channel. This is the stuff we won't ban people for, but would help make things go faster if we didn't have to tell everyone.
* The FAQs are copied from Selvvir. Eventually Selvvir should link to the FAQs and not vice-versa. These are small things that are commonly asked about by all levels of user.
* The Tutorials are for beginners. They are guided introductions to building websites.
* The Documentation is for intermediate and advanced users. They are in-depth coverage of topics, like the w3 specifications.

I think that basically covers all the use-cases for the site.

This is a work-in-progress, please do not merge yet! Discuss changes here and I can fix them before they go live.