[crypto] Encode unicode strings in _cypherer() pycrypto accept both bytes or string but pycryptodome, which will be introduced in next changeset, doesn't accept this. For backward compatibility, encode unicode strings in _cypherer()

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