add "transactional=True", "autorefresh=True" flags to Session; remove SessionTransaction from main docs

[Mike Bayer]

lets make transactional Sessions work like this:

sess = create_session(transactional=True)
.... etc...
sess.close()  # flushes, commits

as well as

sess = create_session()
sess.begin()
... etc..
sess.commit()

i.e. just remove the need to use SessionTransaction explicitly. begin() still returns the SessionTransaction, create_transaction() is deprecated.

[Mike Bayer]

additionally, "autoflush" just adds a flush() call before each query(). that way, when you query(), whatever is pending gets flushed, and the query can then look for objects which were part of that flush. this would imply "transactional" since its best used within a transaction (or better yet, should require the transactional flag be set).

[Mike Bayer]

changeset:2950 changeset:2953

[Mike Bayer]

Removing milestone: 0.4.0 (automated comment)