Revert "use javax.persistence.FlushModeType instead of Hibernate FlushMode"

This reverts commit c70a06a7e90fa61f8344bc51669cb3a84c0673b3.
Revert "Revert "use javax.persistence.FlushModeType instead of Hibernate FlushMode""

This reverts commit 97a2f1ecf7e66546ff23d18ac4458b67c3ad0597.
fix for WEBSITE-252
use withDatastoreSession to avoid unit test problems
fix broken plugin pagination
ugprade oauth plugin
disable social connect buttons pending investigation as to why they don't work
null check for md5 handling
remove disqus tag lib as it is already provided by the disqus plugin
update app version to 2.3.2