= New Adapter

* A swift adapter was added to Sequel.  Swift is a relatively new
  ruby database library, built on top of a relatively new backend
  called dbic++.  While not yet considered production ready, it is
  very fast.  The swift adapter is about 33% faster and 40% more
  memory efficient for selects than the postgres adapter using pg
  with sequel_pg, though it is slower and less memory efficient
  for inserts and updates.

  Sequel's swift adapter currently supports only PostgreSQL and
  MySQL, but support for other databases will probably be added in
  the future.

= Other Improvements

* Sequel now correctly literalizes DateTime objects on ruby 1.9 for
  databases that support fractional seconds.

* The identity_map plugin now handles composite keys in many_to_one
  associations.

* The rcte_tree plugin now works when the model's dataset does not
  select all columns.  This can happen when using the lazy_attributes
  plugin on the same model.

* Sequel now supports INTERSECT and EXCEPT on Microsoft SQL Server
  2005+.

* The Database#create_language method in the shared PostgreSQL
  adapter now accepts a :replace option to replace the currently
  loaded procedural language if it already exists.  This option
  is ignored for PostgreSQL versions before 9.0.

* The identity_map plugin now handles cases where the plugin is
  loaded separately by two different models.

= Backwards Compatibility

* While not technically backwards compatibility related, it was
  discovered that the identity_map plugin is incompatible with
  the standard eager loading of many_to_many and many_through_many
  associations.  If you want to eagerly load those associations and
  use the identity_map plugin, you should use eager_graph instead
  of eager.
