[FEATURE] Add a way to know which user is the creator of a dataset and record

[jfcalvo]

Is your feature request related to a problem? Please describe. Right now we don't have a way to know the user that created a dataset or record.

Describe the solution you'd like A possible solution to this problem is to add a created_by UUID column that store the id of the user that created the dataset. Something similar can be done for records as well.

We should take into account that if this column is not optional we should choose an owner to be set by default.