[wsgi] add message about the active interface Similarly to what done in "stdlib".

[cwctl] rewrite wsgi method choices This will help devs to add new choices by adding their callback to WSGI_CHOICES. Note: ``options`` becomes a property because ``wsgichoices()`` should be evaluated at the last-minute.

[skeleton/debian] use dh_python2 instead of dh_pysupport for new cubes The former is deprecated.

[web] Add source for jquery.qtip.js Downloaded from https://github.com/Craga89/qTip1/raw/master/1.0.0-rc3/jquery.qtip-1.0.0-rc3.js Related to #3851121.