WFS to Shp is done

* need WFS equality service for when to add attributes rather than separate into multiple calls.
finish up the generic part of the exporter, moving on to the portal specific stuff
added portal specific stuff stuff for staging, now just need to hook up REST to staging area
Download hooked up to REST API

* zipping up staging area before starting download
* minor fixes like NPE checks
* added DownloadResource to hook into /data/download/item/{id}
Merge pull request #543 from jiwalker-usgs/downloadItems

Download items thus far