Document that stats won't be recorded if heading does not have a tag

[ParetoOptimalDev]

I was confused for quite a while because of this.

It looks like there is some variable named gamify-stats-instead which could be set to true to make this not the case?

I think it's fine to default to having it work only with tasks that work with tags but can be confusing for a new user.

[Idorobots]

I believe some task that don't have a tag but inherit one implicitly will be recorded, but to be honest, it's been a while since I looked at this code to any extent. Contributions are welcome :)

[Idorobots]

Now I remember that at some point I planned to use hashtags instead. So, normally you go with:

* TODO Integrate SQS into SomeService and write some tests. :AWS:SQS:Golang:Testing:

But with hashtags it's a bit cleaner:

* TODO Integrate #AWS #SQS into SomeService and write some tests. #Golang #Testing.

Never got around to starting this. Any idea if this would be better for your use-case?