DOCS: Describe some missing parameters on CREATE/ALTER PUBLICATION pages

Hi.

I noticed that the CREATE PUBLICATION and ALTER PUBLICATION sysnopses
contain some user-specified parameters which are not defined, and not
even mentioned anywhere else.

For example,

ALTER PUBLICATION
- defines 'name', 'table_name', 'schema_name'
- never mentions 'column_name'

CREATE PUBLICATION
- defines 'name'
- never mentions 'table_name', 'schema_name', 'column_name'

~~~

It seems wrong to include undefined synopsis parameters and just
assume they will be self-explanatory.

It is ad-hoc; some terms are described on one page but not on the other.

~

PSA a small patch to make these parameter descriptions more complete
and consistent.

In passing, I also added some missing <varlistentry> "id"s for the
ALTER PUBLICATION page.

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Kind Regards,
Peter Smith.
Fujitsu Australia