Allow to create materialized views without data

[Mogost]

Please make it possible to create materialized view without data by using WITH NO DATA parameter (optional). https://www.postgresql.org/docs/9.5/sql-creatematerializedview.html

WITH [ NO ] DATA This clause specifies whether or not the materialized view should be populated at creation time. If not, the materialized view will be flagged as unscannable and cannot be queried until REFRESH MATERIALIZED VIEW is used.