* refactor ms planner (renaming, reorganization)
* fix a bug originaly demonstrated by test_version_depends_on
* enhance crossed relation support, though there is still some bug renaming.
some tests were actually wrong.
Buggy tests (wether they fail or not, they are byggy) marked by XXXFIXME)
debian/tmp/usr/lib/PY_VERSION/site-packages/cubicweb/web usr/lib/PY_VERSION/site-packages/cubicweb
debian/tmp/usr/share/cubicweb/cubes/shared/data usr/share/cubicweb/cubes/shared
debian/tmp/usr/share/cubicweb/cubes/shared/wdoc usr/share/cubicweb/cubes/shared