Download navigation UX

Hi

The attached patch is a first cut at part of a larger task that Jonathan
and I have been discussing to improve the UX and simplify the download flow
on the website.

This patch updates the main download page (/download) in a number of ways:

- Wording at the top and in the left menu is simplified, moving away from
"words for the sake of it" as we have now and using more common and easy to
understand terms like "Packages" instead of "Binaries"

- Some images have been updated or replaced to ensure they all have
transparent backgrounds.

- The indented list of binary options with its myriad of links is replaced
with a set of highly visible buttons to choose your distro family - see the
attached initial.png - and then the distribution where applicable:

- The BSD and Linux buttons will display a second set of buttons to
choose the distro when clicked. See linux.png.

- If Javascript is disabled;
- The BSD button will navigate to a new page showing the buttons for
each supported BSD distro.
- The Linux button will navigate to the existing generic Linux page,
where the list of distros at the top has also been replaced with buttons.

This patch does not attempt to sanitise the rest of the download index or
any of the sub-pages at this time. That'll come later.

Comments/bikeshedding?

--
Dave Page
Blog: http://pgsnake.blogspot.com
Twitter: @pgsnake

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