[req] drop from_controller on non WebRequest object (Closes #2901079) The `controller` concept is purely a web things. It does not belong to generic `req` object. The `build_url` code is slightly changed to handle that. This probably requires extended cleanup later. This is a barely used and very internal API. No deprecation period

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