jeremyevans/sequel — pull request #856 by tmtm (2014-08-05 03:14:55+00:00)
Title: FIX: PostgreSQL deadlock sqlstate

In PostgreSQL, when the deadlock error occurs, Sequel::DatabaseError is
raised instead of Sequel::SerializationFailure.
Because the sqlstate of deadlock is '40P01' in PostgreSQL. It is not '40001'.