Saga addWhen return type

If you define a addWhen saga the rule won't be set to active initially. Instead it will wait until the saga resolves and do depending on the return one of the following things:

• ADD_RULE: The rule is set to active
• ABORT: The rule won't be set to active ever
• REAPPLY_ADD_WHEN: starts the addWhen saga again
• ADD_RULE_BEFORE: the rule is set to active before the action happens that was yielded last (Sounds crazy, but you can read how this works). That is usefull if the rule has a target that is the same as the last yielded action