Update URLs

[cmrRose]

Now that our URLs have changed away from "uwex.edu" to "wisc.edu", we will need to change many URLs throughout the application.

[cmrRose]

Places to change:

• emails on the contact page
• footer links
• inline links in the text
• feature services?
• repository readme.md
• anywhere else we can find ".uwex.edu"
• geodata.wgnhs.uwex.edu in the "all sample data" table at the bottom of a sample page, in the urls for thumbnails.