`snooze` is a new tool for waiting until a particular time and then
running a command.  Together with a service supervision system such as
runit, this can be used to replace cron(8).

`snooze` has been tested on Linux 4.2.
It will likely work on other Unix-like systems with C99.

Over cron:
- mnemonic syntax
- no overlapping job runs possible
- filtering by ISO week and day of year
- due to supervision, no centralized daemon required
- due to supervision, can easily disable jobs or force their
  execution instantly
- due to supervision, have custom logs
- due to no centralized daemon, no fuzzing with multiple users/permissions
- very robust with respect to external time changes
- can use a file timestamp to ensure minimum waiting time between two
  runs, even across reboots
- randomized delays (some cron have that)
- variable slack (no need for anacron)
- ad-hoc usage possible, just run the program from command line

Over runwhen:
- less confusing usage (I hope)
- filtering by ISO week and day of year
- zero dependencies

Over uschedule:
- due to supervision, no centralized daemon required
- filtering by ISO week and day of year