cron: cron
In rushkin/bitsandends: Various convenience functions

A makeshift "cron job" functionality

1 2	cron(runfile, frequency = "1 day", start_time = Sys.time(), only_on = NULL, end_time = Inf, dt = 5, verbose = FALSE)

`runfile`	path to the R file to run
`frequency`	a string consisting of an integer, a space, and then one of "seconds", "minutes", "hours", "days", "weeks", "months", "years". Plural form is optional and "sec" and "min" are understood.
`start_time`	datetime object
`only_on`	a vector of weekdays (full names capitalized, e.g. "Sunday"), on which to run. An object of 0 length (e.g. NULL) is equivalent to no restriction.
`end_time`	datetime object or Inf
`dt`	pulse period in seconds. Note that dt should be less than frequency.
`verbose`	logical