Data export based on extent

[capooti]

The download link in the layer info page should export data clipped to the currently selected extent in the map frame.
This shouldn't be that complicated, as the GS WFS GetFeature and WCS GetCoverage supports the BBOX parameter.

[jj0hns0n]

Perhaps a dupe of #389

[jj0hns0n]

Moving to 2.5. Clip and Ship would still be very useful.

[capooti]

I think I will need to work with this in the next days as we really need it urgently. Maybe in the sprint if I have time? So assigning it to me and set back to 2.4 milestone.

[jlautarosilva]

this feature is going to be implemented in 2.4? I offer myself for testing.

[simod]

I don't think it will be.