Code review comment for lp:~hazmat/pyjuju/formula-upgrades-spec

Some additional comments, and a change re. [6]:

[6]

Actually, changing from the previous comments on [6], nevermind
regarding the command name suggestion. upgrade-formula sounds fine
as a way to disambiguate from "upgrade the software/packages".

But then:

[8]

+After the newer formula is in place and before any hooks are executed
+from it, the unit agent will execute the ``upgrade`` hook on the unit
+if present.

Let's name the hook as "upgrade-formula", to match the command name,
and let's reserve the "upgrade" name for package/software upgrades.

[9]

+This allows the formula to process any upgrade concerns it may have
+with regard to upgrading databases, software, etc before its new
+version of hooks are invoked.

We'll need a way to do pre-post logic. Maybe we need a
upgraded-formula hook too, which is executed *after* the new formula
is in place, and then the "upgrade-formula" one is executed *before*
the old one is removed.

What do you think?