[cwvreg] load registry using modules names instead of directories Introspect cubicweb, cubes and apphome using pkgutil to generate the full list of modules names for loading registries. Avoiding using bogus logilab.common.modutils.modpath_from_file().

missing-dep-for-interpreter make => make | build-essential | dpkg-dev (usr/*/cubicweb/skeleton/debian/rules)
embedded-javascript-library usr/share/cubicweb/cubes/shared/data/jquery.js