Add ability to create a materialized view with NO data

[MartinFalatic]

The sql_create_materialized_view schema ends WITH DATA - it would be useful in certain cases to create a materialized view using WITH NO DATA so that it isn't populated until some subsequent refresh (this avoids a lengthy pause in a deployment when a materialized view would take a significant amount of time to repopulate). The only workaround currently is to bypass this library and use direct SQL commands.