def fetch
      VersionsFile.load(read_file(Configuration.versions_file),
                        read_file(Configuration.prerelease_versions_file, true))
    end
def fetch
      VersionsFile.load(read_file(Configuration.versions_file),
                        read_file(Configuration.prerelease_versions_file, true))
    end
@param [Source] source


 @return [Gemirro::VersionsFile]