[entities] Introduce an IDublinCore adapter Move all dc_ methods from AnyEntity to the new IDublinCore adapter and proxy them through a __getattr__ method on AnyEntity. Current test suite should be enough. Closes #3119992.

[skeleton] Add an entry point and configuration for running a Pyramid application We add a `pyramid_main` function in __init__.py that instantiate the WSGI application using "cubicweb.pyramid"; this is defined as an entry point (in setup.py) so that pserve_ can find it. Alongside comes a development.ini file which includes basic settings so that running a Pyramid+CubicWeb application works (only the "instance=<appid>" may be passed as a command-line argument). Logging is also configured there, but only includes the cube at stake and cubicweb (others could be added if needed). .. _perse: \ http://docs.pylonsproject.org/projects/pyramid/en/1.8-branch/pscripts/pserve.html