Put metadata

    prop : string
        name of property
    val : string
        value to set

    CLI Example:

    .. code-block:: bash

        salt '*' mdata.list

def put_(keyname, val):
    '''
    Put metadata

    prop : string
        name of property
    val : string
        value to set

    CLI Example:

    .. code-block:: bash

        salt '*' mdata.list
    '''
    mdata = _check_mdata_put()
    ret = {}

    if mdata:
        cmd = 'echo {2} | {0} {1}'.format(mdata, keyname, val)
        ret = __salt__['cmd.run_all'](cmd, python_shell=True, ignore_retcode=True)

    return ret['retcode'] == 0