emphasizing navigation paths, updating text, and adding feed & social icons/links

To emphasize navigation paths, especially for new users I:

 * moved navigation links above the search box and shortened the vertical thickness of the legend bar so that the links are much more likely to appear above the fold

 * simplified the number and titles of links, again with new users in mind

Text updates included:

 * cutting up the big paragraphs into smaller thematic chunks so they are easier and more inviting to skim

 * pulling in text from our most recently completed proposal narrative to keep our story up-to-date

 * I defined words that some commentators have said are "confusing" (gazetteer, graph)

I added the following icons with links (and hover text):

 * a round, blue (geo)rss icon to the right-hand end of the legend bar above the map (links to the "recent items" rss feed)

 * three rectangular icons to the left-hand end of the footer bar: orange RSS (linked to our blog's feed), white flickr (linked to an "any pleiades machine tag" query), and blue twitter (linked to a search of our #adfines hashtag)

I also did a little fiddling with text styles (lower-casing a couple of things that are not really sentences and that stand alone in the layout).