[adapters] move class EntityAdapter from cubicweb.view to cubicweb.entity
The adapter mechanism is not specific to the use of views. Moving the
class the cubicweb.entity makes this clearer.
.. _appobject_module:
:mod:`cubicweb.appobject`
=========================
.. automodule:: cubicweb.appobject
.. autoclass:: AppObject
:show-inheritance:
:members: