'Return a command list with all found options.
:param variables_dict: Pre-parsed optional variables used from a
seed command.
:type variables_dict: ``dict``
:param build_command: Command to run.
:type build_command: ``list``
:returns: list of command options.
:rtype: ``list``'

@staticmethod
def _add_variables(variables_dict, build_command):

    for (key, value) in variables_dict.items():
        build_command.append(('%s    %s' % (key, value)))
    else:
        return build_command
