Add EI_clustered_network by Rostami et al to PyNEST examples

[schmitfe]

We added a PyNEST example to simulate an EI-clustered network ¹. The example has a similar structure as Potjans_2014 PyNEST example. We provide a short readme and documented source code.
After introduction of the high-level routines to create clustered connectivity, this example might be a good candidate to use them.

Footnotes

1. Excitatory and inhibitory motor cortical clusters account for balance, variability, and task performance
   Vahid Rostami, Thomas Rost, Alexa Riehle, Sacha J. van Albada, Martin P. Nawrot
   bioRxiv 2020.02.27.968339; doi: https://doi.org/10.1101/2020.02.27.968339 ↩

[jessica-mitchell]

Hi thanks for your contribution! I have a few changes requested along with a Pull request made against your branch to add the example to the index page in the docs.

[jessica-mitchell]

@schmitfe thanks for the updates, can you fix the conflicts in the CI please? We encourage the developers to set up a pre-commit hook that will check isort/black etc automatically when a commit is made. Take a look at our developer tools for info on that.

[schmitfe]

@heplesser I was able to change the raster_plot.py to include color groups and think the changes did not introduce any changes to its behavior if no colorgroups are provided. But the change might still need some discussion and refinement.
Should I create another pull request with the change of the raster_plot or an issue, or just include it within this pull request?

Right now I put it into a new branch:
https://github.com/schmitfe/nest-simulator/tree/add_color_groups_raster_plot
There I changed the raster_plot.py and added brunel_alpha_nest_raster_color_groups.py in the examples which uses the new functionality. The current version is quite slow if color groups are used in larger networks. I was also not sure if it makes sense to change also the behavior for the histogram in this case to only contain actual plotted neuron IDs and/or split into one for each color group.

[heplesser]

@schmitfe Thank you very much for the very thorough revision of the example. It looks good to me now, I just have a few suggestions on details.

@jessica-mitchell Could you take a look as well?

[jessica-mitchell]

Thanks for your contribution @schmitfe ! I have one small change and ask that you resolve the conflict, but otherwise it looks good. The example runs on latest EBRAINS release too.

[schmitfe]

Thanks for your contribution @schmitfe ! I have one small change and ask that you resolve the conflict, but otherwise it looks good. The example runs on latest EBRAINS release too.

Thanks for checking. I just corrected the wrong copyright header. Now all the checks should pass.

[heplesser]

@schmitfe Thanks a lot, all fine now, just the tests need to go through and we are good to merge.