[pkg] Add development.ini.tmpl to "cubicweb.pyramid" package data
Otherwise the file is not installed and `cubicweb-ctl create -c pyramid` does
not work.
[skeleton] Don't use system site packages in tox environment
As we changed this in cubicweb, there is a consensus that this
is not the best practice so let us change it as well for
skeleton.
[doc] Update "settings" pyramid documentation
Document that without "bwcompat" we can use a development.ini file directly
and add a dedicated section to list configuration options.