20110912
========

The following two changes came because it took me a rather long time
to understand why the Detail of the new `dsbe.jobs.Offer` model 
complained about not finding the `jobs.PersonsByOffer`
slave report. Explanation that this was called
`contacts.PersonsByOffer` according to my own rules established
:blogref:`20110822`.

The `app_label` of a Report
---------------------------

I changed (again) the rules for setting the `app_label`
of a Report:

The default value (which should be used in most cases) is
the "application" where the Report is defined.
For example it's now
`dsbe.MyPersons` and not `contacts.MyPersons`,
`dsbe.LinksByPerson` and not `links.LinksByPerson`,
`lino.ContentTypes` and not `contenttypes.ContentTypes`...

Enhanced the message of the exception risen when an unknown
element name is found in a :xfile:`.dtl` file: it also now
tells us the possible values, including slave reports.


`makedocs` got better
---------------------

:mod:`lino.management.commands.makedocs`
got a bit better.
The result is at
:lino:`/dsbe/appdocs`
and
:lino:`/igen/appdocs`
(but is not yet production ready).