Oracle requires us to close our connections after each
request (or else implement a connection pool), otherwise
we will end up running out of available connections.
While the mechanism for doing this was added in a previous
change, actually using it correctly was omitted somehow.
Fix that now.
git-svn-id: http://webgoat.googlecode.com/svn/trunk@233 4033779f-a91e-0410-96ef-6bf7bf53c507