Added call to retrieve hypoxic extent when the May load for the fake
site is requested. Modified LoadPlot.js to show the extent when data is
available.

Removed detailed and summary links from id popup when the fake site is
selected. 

Pass in to GraphPopup.create only the staname and id. Set these
correctly for the fake site.
Passing in a siteId = "GULF" for the virtual site. Also passing is
isVirtual so that the fake site ID is only hard coded in
mississippi/main.js.
Merge pull request #262 from mbucknell/NAWQAAN-367

Nawqaan 367