postgres_fdw incomplete examples

The following documentation comment has been logged on the website:

Page: https://www.postgresql.org/docs/10/static/postgres-fdw.html
Description:

The examples about postgres_fdw do not tell about the need to have a HANDLER
when we want to access foreign tables. There should be indications on how to
build a handler, especially on loopback FDW (postgres-to-postgres like
dblink).