Add basic interrupt to pomodoro
Add interrupts controller
Implement `par pomodoro interrupt`. Alias it to `par interrupt`.
Use kind_of? instead of comparing classes
Add number of interrupts to report
Update TODOs
Add AbstractInterrupt
Simplify Interrupt types
Pass interrupt type from controller to pomodoro
Distinguish internal and external interrupts
Make PAR_POMODORO_ID and PAR_BREAK_ID available to before hooks
Remove delete. It isn't really needed nor tested.
Implement `before-interrupt-pomodoro` and `after-interrupt-pomodoro` hooks
Add TODO about interrupt status
Add unit tests for Pomodoro.cancel
Implement Pomodoro.cancel
Add tests for status
Model interrupt as state
Add cancel to controller
Add cancel to bin script.