Log Message:
databases/ruby-sequel: update to 5.28.0

=== 5.28.0 (2020-01-01)

* Warn when calling Sequel::JDBC::Postgres::Dataset#with_fetch_size \ 
(jeremyevans) (#1665)

* Add exclude_or_null extension, for filtering datasets where the condition is \ 
false or NULL (jeremyevans)

* Add any_not_empty extension, for making Dataset#any? without a block mean \ 
!empty? (jeremyevans)

=== 5.27.0 (2019-12-01)

* Add Sequel::DEFAULT for a DEFAULT expression, useful for assigning to default \ 
values (jeremyevans)

* Make Postgres::ArrayOp#join in pg_array_ops extension work correctly on \ 
PostgreSQL <9.1 (jeremyevans)

* Make pg_enum extension work correctly on PostgreSQL 8.3-9.0 (jeremyevans)

* Emulate FILTER clause for aggregate functions using CASE on databases not \ 
supporting it directly (jeremyevans)

* Support ordering by NULLS FIRST/NULLS LAST without emulation on SQLite 3.30+ \ 
(jeremyevans)