[test] drop dependency on third party cubes Drop dependency on cubicweb-file, cubicweb-localperms, cubicweb-tag and cubicweb-comment for cubicweb.test and cubicweb.sobjects.test Move cubicweb/test/data/libpython/cubicweb_* to cubicweb/test/data, so it's included in PYTHONPATH. Add missing parts of schema, entities, views, hooks that make tests pass.

if repo.system_source.dbdriver == 'postgres':
    sql('ALTER TABLE appears ADD COLUMN weight float')
    sql('UPDATE appears SET weight=1.0 ')