pg_dump, pg_dumpall, pg_restore: Add --no-policies option

pg_dump[all] and pg_restore have a lot of "--no-XXX" options,

I noticed there is no "--no-policies"; the patch implements it for pg_dump,
pg_dumpall, and pg_restore.

This can be useful in scenarios where policies need to be redefined in the
target system or when moving data between environments with different
security requirements.

Looking for feedback.

Nik