add cli using Click

[golgor]

Is your feature request related to a problem? Please describe.
Now there is no interface and no way to control the pomodoro timer.

Describe the solution you'd like
A clear and easy CLI interface. Preferably also with count down until timer is out as well as different options to extend time or add breaks.

Describe alternatives you've considered
Web interface is another solution.

Additional context
Updated later.