Add spotlight nest

Closes #338 (closed)

The NEST simulator (Helmholtz research field: Information) is a spiking neural network simulator for neuroscience research.

• Review link

Checklist for authors

• Add a link pointing to the review app

Checklist for reviewers

• Reference the corresponding issue in MR
• File size of images is not too large
• Update date_added attribute
• Centres are referenced by official names
• License is named by SPDX identifier if possible
• All links are pointing to the right place

/cc @frust45 @konrad @jandt-desy @christian.meessen

_spotlights/nest.md

@@ -24,8 +24,9 @@ date_added: 2022-06-30
 preview_image: nest/nest_logo.png
 
 # One or two sentences describing the software
-excerpt: NEST is a simulator for spiking neuronal networks. A well tested and efficient tool, NEST
-works on your laptop and also on the world’s largest supercomputers to study behaviour of large networks of neurons.
+excerpt: >
+  NEST is a simulator for spiking neuronal networks. A well tested and efficient tool, NEST
+  works on your laptop and also on the world’s largest supercomputers to study behaviour of large networks of neurons.
 
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 # Properties for individual spotlights page