NS: [tool]: Probabilities tool connection across subregion issue for v2.0

[drdiek]

Typically cross-subregion neuron types will be from different subregions but their connection dendrites and axons will be in 1 subregion (and different layers in the subregion). Having to calculate and report results from axons and dendrites in 2 subregions for a connection is not currently reporting results correctly in the probabilities tool. Currently, this appears to only affect the connection with neuron ids 2020 to 3007. A notice has been programmed so that if the tool use tries to retrieve values from that connection it reports on the tool page that the values are not reported correctly. The 2020 -> 3007 connection is only 1 of ~3000 connections the tool computes values for. This issue perhaps only affects the probabilities tool and not other calculations reported for results with the synaptic probabilities project. If further connections spanning more than one subregion are added in the future to the tool this may become a more noticeable issue than only 1 in ~3000 connections. Because it is an uncommon issue currently this is a minor issue.