[skeleton,pyramid] Move pyramid app definition in cubicweb.pyramid module
The application definition is actually not specific to the final "cube" being
bootstrapped from skeleton. This patch thus move the pyramid application
function into cubicweb.pyramid module and let cubicweb register the
"paste.app_factory" entry point (instead of the bootstrapped cube).
Useless call to `config.scan` is dropped along the way.
^build$
^dist$
\.egg-info$
^.tox$
^.cache$
\.pyc$
\.pyo$
\.bak$
\.old$
\~$
\#.*?\#$
\.swp$
^doc/book/en/apidoc$
\.old$
\.pybuild
debian/python-cubicweb
debian/*.log
debian/*.substvars
debian/cubicweb-doc
debian/cubicweb
debian/files
syntax: regexp
.*/data.*/database/.*
.*/data/ldapdb/.*
.*/data/uicache/
.*/data/libpython/cubicweb_.*/i18n/.*\.po
^doc/html/
^doc/doctrees/
^doc/book/en/devweb/js_api/
^doc/_build
^doc/js_api/
test-results.xml