_project.py: Use utils' search upwards helper when searching for project.conf

    #    LoadError if project.conf is not found

    #    LoadError if project.conf is not found

    #

    #

    def _find_project_dir(self, directory):

    def _find_project_dir(self, directory):

        directory = os.path.abspath(directory)

        project_directory = utils._search_upward_for_file(directory, _PROJECT_CONF_FILE)

        while not os.path.isfile(os.path.join(directory, _PROJECT_CONF_FILE)):

        if not project_directory:

            parent_dir = os.path.dirname(directory)

            # TODO: We can also find the project dir through a workspace

            if directory == parent_dir:

            raise LoadError(

            raise LoadError(

                LoadErrorReason.MISSING_PROJECT_CONF,

                LoadErrorReason.MISSING_PROJECT_CONF,

                '{} not found in current directory or any of its parent directories'

                '{} not found in current directory or any of its parent directories'

                .format(_PROJECT_CONF_FILE))

                .format(_PROJECT_CONF_FILE))

            directory = parent_dir

        return directory

        return project_directory

    def _load_plugin_factories(self, config, output):

    def _load_plugin_factories(self, config, output):

        plugin_source_origins = []   # Origins of custom sources

        plugin_source_origins = []   # Origins of custom sources