Merge pull request #108 from cdmiller/master

ShipOdyssey v2013.07.19: make Mission attribute in DG a string, was a nu...
Ship Odyssey: update for Issue #109: old cases not closed, preventing Clear Data.
Added a fix plus debugging statements to detect the problem more generally.
This fix works, but there may be more issues when integrated with the new buttons to go to the next site.