[IMP] unwrap tests suites during module loading, prepare for storing/filtering attributes
[ADD] hooks to enable/disable tests running during install

also add flag for post_install run, but not used yet
[FIX] run_unit_tests lying about its return value: it only ever returns a bool, never None
[IMP] slightly improve error message at the end of a module's failed tests
Merge branch 'master' of bzr::lp:openobject-server