[test/tox] Enforce installation of modified yapps
580a6821713d is not enough for tox apparently...
The thing is that it will first install dependencies (the `deps` option from
tox.ini), actually pulling yapps from Logilab github but then, it will install
the project (that is, CubicWeb) from the sdist *along with its dependencies*,
which will pull yapps again and override the previously installed version for
some mysterious reason.
So add a `pip install` command in tox.ini, so that the modified yapps is the
last one installed.
Schema of the data
------------------
First take a look at the data schema_ then try to remember that you are browsing
through a heap of data by applying stylesheets to the results of queries. This
site is not a content management system with items placed in folders. It is an
interface to a database which applies a view to retreived data.
.. _schema: ../schema