OSX mirror page slightly confusing

[embray]

Had a user who was confused when clicking through the Mac download links, and I agree it was confusing:

E.g. from http://www.sagemath.org/download-mac.html when one selects a mirror they are first asked to choose between intel and ppc: http://www.mirrorservice.org/sites/www.sagemath.org/osx/intel/index.html

They had no problem with this part, though it should probably be skipped because PPC is no longer supported. Instead it should go straight to intel; maybe with a small link at the bottom to find old PPC builds.

But the next page was confusing:

http://www.mirrorservice.org/sites/www.sagemath.org/osx/intel/index.html

Before the downloads for the recent versions there are links for subdirectories "development" and "old". The user thought they had to choose between one of those (as they did intel vs ppc) and on a relatively small screen the subdirectory links are big enough that it's easy to miss the download links below them. I suggest moving those links to the bottom of the page instead, and also note that the top-most links are for the most recent version of Sage.

[kcrisman]

Agreed that we need a lot of TLC for the download pages.