Proposal #1: ImageMosaic FeatureInfo enrichment

The goal of this proposal is simple but interesting. We have been asked to try and give access not only to pixel values during a GetFeatureInfo but also to the additional attributes of the associate record from the underlying mosaic index. This is of course challenging, as an instance:

1. we need to minimize the number of requests to reduce or eliminate the impact on performances
2. we shall not show the FID and geometry coming from the index
3. should we hide the location? If so, how do we spot it? (We cannot assume anything about its property name in the db)

There is a corresponding proposal in GT to collect the simplefeature as we process them to create the mosaic, notice that this process for the moment works in immediate mode not in streaming, hence by default is deactivated.