Merge pull request #6 from timf/H2PR

Concurrency improvements
Merge pull request #7 from timf/H2PR

Deleted extra log statement
Merge pull request #8 from timf/H2PR

cache JNDI lookups
[maven-release-plugin] prepare release dasein-persist-2013.02
[maven-release-plugin] prepare for next development iteration
Better slow query log messages