[Discussion] Improve/Redo storage of incidents

Alright, this is going to be a hard one:
As said in the deliverable, `The system will only store a selection of incidents (those submitted by a person or entity, or some specific values submitted by sensors, not all of them).`, and `Incidents can also have an expiration, for example, in the case of the incidents submitted by a
temperature sensor, if they are submitted each hour, the expiration time will be an hour).`.
In #22 we took the approach of using a JSON configuration file to know which incidents must / must not be saved. We talked with labra about this, and he said this was not a very elegant solution, so we should think of another way of accomplishing this.
Right now I can't think of any better way of doing this, so I opened this issue so everyone can tell their ideas and what we should do about this (leave it like it is but implement the expiration date, improve the existing implementation...).