write tests

[calin-darie]

Gentle Glow has reached the level of complexity where putting all the code in the view as if for a simple demo is no longer maintainable and there are enough use cases for each possible action to mentally test and debug.

With the addition of the schedule #6 , the level of complexity will explode.

Tests need to be written for both these reasons: to support an inevitable refactoring short-term, as well as refactorings to come, and to manage increasing complexity.