[hibernate-dev] Rebased ORM6

I've completed a rebase of Steve's latest ORM6 branch onto our latest ORM5 master, so to have it incorporate all latest bugfixes and performance enhancements we recently developed on master. To be more specific, this is a rebase of commit 'wip/sqm-jpa-types-sql-ast' [2e002c73c6] onto 'master' [40b30fa099]. I'm pushing it as branch '6-rebased-August' to my own fork. (commit [ec3a325fbc]). I hope that anyone having some work in progress could cherry pick on top of that :) Also you probably want to push it somewhere else and give a more creative name. Steve: the last commit might need special attention. I needed to review the SessionImpl#buildLockOptions method as there was a conflict, but while trying to resolve it I realized the method was probably not doing what it was supposed to, so I changed it - I think fixing something odd but I might have misunderstood the intent, or thrown off by some mistake during rebase. Would appreciate another pair of eyes on that one as I definitely changed the semantics. Thanks, Sanne