[test] pull yapps from Logilab's github Fixes a couple of failures, pull request is almost a year old (https://github.com/smurfix/yapps/pull/2).

version=3
opts=uversionmangle=s/(rc|a|b|c)/~$1/ \
http://pypi.debian.net/cubicweb/cubicweb-(.+)\.(?:zip|tgz|tbz|txz|(?:tar\.(?:gz|bz2|xz)))