This field follows the syntax of cron (with minor differences). Specifically, each line consists of 5 fields separated by TAB or whitespace:
    MINUTE HOUR DOM MONTH DOW
    MINUTE	Minutes within the hour (0-59)
    HOUR	The hour of the day (0-23)
    DOM	The day of the month (1-31)
    MONTH	The month (1-12)
    DOW	The day of the week (0-7) where 0 and 7 are Sunday.
    To specify multiple values for one field, the following operators are available. In the order of precedence,

    '*' can be used to specify all valid values.
    'M-N' can be used to specify a range, such as "1-5"
    'M-N/X' or '*/X' can be used to specify skips of X's value through the range, such as "*/15" in the MINUTE field for "0,15,30,45" and "1-6/2" for "1,3,5"
    'A,B,...,Z' can be used to specify multiple values, such as "0,30" or "1,3,5"
    Empty lines and lines that start with '#' will be ignored as comments.

    In addition, '@yearly', '@annually', '@monthly', '@weekly', '@daily', '@midnight', and '@hourly' are supported.

    Examples
    # every minute
    * * * * *
    # every 5 mins past the hour
    5 * * * *