Store event values

Issue #22 resolved
created an issue

An event currently doesn't store the value with which it has been triggered. I was concerned that this reference to the value would lead to memory hogging. However I've encountered many usecases in which it would be extremely convenient to access the result of an event after it has been processed (conditions are one example).

Stefan, I remember that you were in favor of storing the event values? If this is still true, I will create a fork to experiment with this idea.