Re: Pluggable toaster

Hi Nikita,

Thanks for an update!

> 0002_toaster_interface_v10 contains TOAST API with Dummy toaster as an example (but I would,
> as recommended, remove Dummy toaster and provide it as an extension), and default Toaster
> was left as-is (reference implementation).
>
> 0003_toaster_default_v9 implements reference TOAST as Default Toaster via TOAST API,
> so Heap AM calls Toast only via API, and does not have direct calls to Toast functionality.
>
> 0004_toaster_snapshot_v8 continues refactoring and has some important changes (added
> into README.toastapi new part related TOAST API extensibility - the virtual functions table).

This numbering is confusing. Please use a command like:

```
git format-patch origin/master -v 42
```

This will produce a patchset with a consistent naming like:

```
v42-0001-foo-bar.patch
v42-0002-baz-qux.patch
... etc ...
```

Also cfbot [1] will know in which order to apply them.

> GIT branch with this patch resides here:
> https://github.com/postgrespro/postgres/tree/toasterapi_clean

Unfortunately the three patches in question from this branch don't
pass `make check`. Please update
src/test/regress/expected/publication.out and make sure the patchset
passes the rest of the tests at least on one platform before
submitting.

Personally I have a little set of scripts for this [2]. The following
commands should pass:

```
# quick check
./quick-build.sh && ./single-install.sh && make installcheck

# full check
./full-build.sh && ./single-install.sh && make installcheck-world
```

Finally, please update the commit messages. Each commit message should
include a brief description (one line) , a detailed description (the
body), and also the list of the authors, the reviewers and a link to
the discussion. Please use [3] as a template.

[1]: http://cfbot.cputube.org/
[2]: https://github.com/afiskon/pgscripts/
[3]: https://git.postgresql.org/gitweb/?p=postgresql.git;a=commit;h=784cedda0604ee4ac731fd0b00cd8b27e78c02d3

--
Best regards,
Aleksander Alekseev