close the dao when the AmberSession is closed (it calls shutdown on AmberGraph)
Merge branch 'master' of github.com:nla/amberdb into close-session
version bump
2 processes accessing the same session could commit the same NEW element as current in the persistent store. Now, the last commit end-dates any previous commits. This behaviour should probably be reviewed to decide if it's the one we want, but it will prevent inconsistencies in the database in the meantime.
Merge pull request #103 from nla/double-commit

Double commit