An activation event logged by the WorkingMemoryLogger.
It is a snapshot of the event as it was thrown by the working memory.
It contains the activation id, the name of the rule and a String
representing the declarations of the activation, which is a list of
name-value-pairs for each of the declarations in the tuple of the
activation. The name is the identifier (=name) of the
declaration, and the value is a toString of the value of the
parameter, followed by the id of the fact between parentheses.
e.g. param1=10; param2=Person[John Doe]
Such a String representation is used to create a snapshot of the
current state of the activation by storing a toString of the facts
bound in the activation. If necessary, this event could be extended
to contain a map of declarations too.
