Drop most deprecated code in cubicweb.web This includes both Python and JavaScript code. Most code has been deprecated since a very long time (versions 3.1x mostly, more than 5 years ago, and a few things until 3.24). There are still a few deprecated things, most of which are actually used within cubicweb (or in cubes we depend on for tests). I don't know what to do with these... Removed a couple of unused imports along the way. Changelog entry will come in a later changeset.

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