Use TypeName to represent type names in certain commands

In COMMENT, DROP, SECURITY LABEL, and the new pg_get_object_address
function, we were representing types as a list of names, same as other
objects; but types are special objects that require their own
representation to be totally accurate.  In the original COMMENT code we
had a note about fixing it which was lost in the course of c10575ff005.
Change all those places to use TypeName instead, as suggested by that
comment.

Right now the original coding doesn't cause any bugs, so no backpatch.
It is more problematic for proposed future code that operate with object
addresses from the SQL interface; type details such as array-ness are
lost when working with the degraded representation.

Thanks to Petr Jelínek and Dimitri Fontaine for offlist help on finding
a solution to a shift/reduce grammar conflict.
Fix object_address expected output

Per pink buildfarm
Add pg_identify_object_as_address

This function returns object type and objname/objargs arrays, which can
be passed to pg_get_object_address.  This is especially useful because
the textual representation can be copied to a remote server in order to
obtain the corresponding OID-based address.  In essence, this function
is the inverse of recently added pg_get_object_address().

Catalog version bumped due to the addition of the new function.

Also add docs to pg_get_object_address.
pg_event_trigger_dropped_objects: Add name/args output columns

These columns can be passed to pg_get_object_address() and used to
reconstruct the dropped objects identities in a remote server containing
similar objects, so that the drop can be replicated.

Reviewed by Stephen Frost, Heikki Linnakangas, Abhijit Menon-Sen, Andres
Freund.
Merge branch 'master' of git://git.postgresql.org/git/postgresql into psql_fix_uri_service
Prevent tab completion for \c to URI and service