* Add a new function zope.sqlalchemy.register(), which replaces the
  direct use of ZopeTransactionExtension to make use
  of the newer SQLAlchemy event system to establish instrumentation on
  the given Session instance/class/factory.   Requires at least
  SQLAlchemy 0.7.
Merge pull request #4 from zzzeek/master

add new register() function to establish zope listener via SQLAlchemy events