[importer] Implement rake task to create importer schema for those users that don't have it
clean up
[importer] Assign cdb_importer schema using User#set_database_permissions_in_importer_schema

Conflicts:
	app/models/user.rb
	spec/models/user_spec.rb
[importer] Report progress in rake task to create the schema for the importer
Fix cherry-pick