multiple point to isec converter

[arnaudon]

This is a proposal PR to allow for converting a list of 3d points to a list of neuron isections with multiprocessing. This can be used to process a large number of morphologies, and requires each computation to be isolated to prevent NEURON clashes with itself.

Things to do/discuss:

• is this the correct place?
• shall we add an app?
• it needs some tests
• it may assume too much from the file structure, etc... for a generic user
• the isolating functions should be used for any NEURON based computations in parallel, so it may serve for other functions in the package. It may be worth moving these (along with NestedPool) to a utils.py?

[arnaudon]

So you don't want to keep the isection converter here? Tbh, I think it is better to not have to do this step, and only record the coordinate of apical point, and convert to whatever is needed wherever it is needed. So we could update the PR purpose.

For isolate, I need to double check, but I think NestedPool is not needed to isolate, but only to run the isolated functions in parallel. I have now a dask setup for running isolated functions in parallel, which only needs a config modification rather than this NestedPool.

[arnaudon]

Ah sorry, I forgot about that one, you can merge as it is, I think it is fine. The apical point thing will be done differently anyway.