DROP VIEWs in Release 18

[Manos Tsagkias]

In the update instructions to Release 18, the command:

grep 'VIEW' sql-extra/CreateSimpleViews.sql | sed 's/CREATE OR REPLACE/DROP/' | sed 's/ AS/;/' | ./mbslave-psql.py

gives this error in Postgres 9.2:

ERROR:  cannot drop view s_release_country because other objects depend on it
DETAIL:  view s_first_release_country depends on view s_release_country
HINT:  Use DROP ... CASCADE to drop the dependent objects too.

I fixed the error, editing the command to be:

grep 'VIEW' sql-extra/CreateSimpleViews.sql | sed 's/CREATE OR REPLACE/DROP/' | sed 's/AS/CASCADE;/' | ./mbslave-psql.py