Return information about a group

    CLI Example:

    .. code-block:: bash

        salt '*' group.info foo

def info(name):
    '''
    Return information about a group

    CLI Example:

    .. code-block:: bash

        salt '*' group.info foo
    '''
    if salt.utils.stringutils.contains_whitespace(name):
        raise SaltInvocationError('Group name cannot contain whitespace')
    try:
        # getgrnam seems to cache weirdly, so don't use it
        grinfo = next(iter(x for x in grp.getgrall() if x.gr_name == name))
    except StopIteration:
        return {}
    else:
        return _format_info(grinfo)