Conversion of Git data in events

[sduenas]

We want to make events first-class data so most of the analysis are performed using them.
In GrimoireLab. we had other approaches for converting data into events in the past. The cereslib library had this task. Data would be fetched and stored, and at some point, it would be converted into events.

We would like to change this workflow and start generating events right after data is fetched. For this goal, we will have to create a new tool/library that can be integrated with the new scheduler we are developing.

The first step will be to generate the events of the Git datasource.