Allow to start unrestricted Pomodoro

[kamilprusko]

Idea submitted by Dinesh through website / disqus comments and it's inspired by https://bluebird.app/guide .

Allow to start the timer with time tracking, possibly reducing distractions as during regular Pomodoro. The timer would display elapsed time in such mode, or in other words - would be counting up.

[kamilprusko]

In research studies it's often called as "Self-paced" session, and for some people there are some benefits of not forcing a break (time-boxing).