[web form] refactor Form.__init__ so that extra kwargs are set earlier in the process. Closes #2443040
(eg if you want to use them in .session_key)
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