panel methods should return Events

[neuromusic]

panel.reward() & panel.punish() should return Event classes specifying the time and duration of the event

[neuromusic]

I'm open to discuss this.

My idea here was that any event that we want to track should be represented as a standard object, like we've setup the Stimulus objects. Then, in addition to saving Trials as we currently do in the csv, we could save every single Event which occurs in a separate store (json, a la tinydb?), along with a pointer to the associated Trial.