Fix CreatePolicy, pg_dump -v; psql and doc updates

Peter G pointed out that valgrind was, rightfully, complaining about
CreatePolicy() ending up copying beyond the end of the parsed policy
name.  Name is a fixed-size type and we need to use namein (through
DirectFunctionCall1()) to flush out the entire array before we pass
it down to heap_form_tuple.

Michael Paquier pointed out that pg_dump --verbose was missing a
newline and Fabrízio de Royes Mello further pointed out that the
schema was also missing from the messages, so fix those also.

Also, based on an off-list comment from Kevin, rework the psql \d
output to facilitate copy/pasting into a new CREATE or ALTER POLICY
command.

Lastly, improve the pg_policies view and update the documentation for
it, along with a few other minor doc corrections based on an off-list
discussion with Adam Brightwell.

src/backend/commands/policy.c

@@ -556,7 +556,7 @@ CreatePolicy(CreatePolicyStmt *stmt)
 
 	values[Anum_pg_rowsecurity_rsecrelid - 1] = ObjectIdGetDatum(table_id);
 	values[Anum_pg_rowsecurity_rsecpolname - 1]
-		= CStringGetDatum(stmt->policy_name);
+		= DirectFunctionCall1(namein, CStringGetDatum(stmt->policy_name));
 
 	if (rseccmd)
 		values[Anum_pg_rowsecurity_rseccmd - 1] = CharGetDatum(rseccmd);