New, smaller but expandable intro

[ericvalcik]

I've changed the intro, as we discussed on a call a while ago.

Changes:

• Removed the three boxes under the intro
• Added another paragraph with a link to our faq.
• The intro on load (with javascript enabled) only shows the second paragraph but can be expanded fully

I pretty much copied the text from the previous intro, but the contents of the first and the third box are no longer present. I don't think we really need to mention feedback possibilities (like we used to in the third box) in the intro as we already have the floating card on the left side, but maybe the information from the first box is nice to have there. I wanted to keep the intro brief so I didn't include this part, but it could be easily added.

[mukrop]

How is this going on? We'll have a presentation at DevConf.CZ by the end of next week and I'd prefer to have this deployed by then :-).