db versioning error

git-svn-id: https://plugins.svn.wordpress.org/an-gradebook/trunk@1025534 b8457f37-d9ea-0310-8a92-e5e31aec5664
db versioning error yet again

git-svn-id: https://plugins.svn.wordpress.org/an-gradebook/trunk@1025536 b8457f37-d9ea-0310-8a92-e5e31aec5664