Add a fuzzy version of the AggJoiner

[rcap107]

Problem Description

The current implementation of the AggJoiner executes an exact left join between the main table and the aux table. It would be useful to have a "fuzzy" version of this that allows to aggregate the "fuzzy" groups that are found using the machinery implemented in the Joiner.

This would be very useful with geographical data, for example: by using latitude and longitude as join keys, it would become possible to aggregate new features based on the neighborhood of a sample in the main table.

Feature Description

This could be either a new object (FuzzyAggJoiner?), or be implemented as a flag in the current AggJoiner.
At join time, rather than using the current implementation, the groups identified by the Joiner should be used to find the aggregations and the new features should be added.

Alternative Solutions

No response

Additional Context

No response