[Systems] Better links bar for wiki.sugarlabs.org

[Bernie Innocenti]

Dogi noticed that we had two "Download" links in the Wiki: one on the
sidebar, leading to the download page, and one in the links bar on top
of the page which leads straight to download.sugarlabs.org.

In the name of clarity, I removed the Download link on top, along with a
few other links to developer oriented resources. Those are still easy to
find from either git.sugarlabs.org or bugs.sugarlabs.org.

I also tried to make the links bar prettier and more visually distinct
from the rest of the page. Anyone with better designer skills feel free
to improve it further. I think it would be best if we could consolidate
on on the same look across all services, like Google does for its
navbar.

I have also another thought, more controversial: the content of our
static website is very outdated and I heard complaints about it from
many people (especially casual visitors). Meanwhile, several people
worked on improving the visual look, usability and content of the wiki.
Wouldn't it be better to make the wiki become our website?

The marketing team could probably come up with a refreshed version of
the website, but it might take a long time to finalize it. I see this as
a temporary solution.

-- 
   // Bernie Innocenti - http://codewiz.org/
 \X/  Sugar Labs       - http://sugarlabs.org/