Add Allen Institute Brain Modeling Toolkit (BMTK) / SONATA

[rly]

https://github.com/AllenInstitute/bmtk

[oruebel]

Relevant resources:

• Documentation describing using NWB with BMTK: https://alleninstitute.github.io/bmtk/ecephys_probe.html
• Brief abstract describing the tools: https://www.braininitiative.org/toolmakers/resources/brain-modeling-tools-bmtk-sonata-vnd/
• Additional information: Tutorials on using BMTK https://alleninstitute.github.io/bmtk/tutorials.html
• Source: https://github.com/AllenInstitute/bmtk

[oruebel]

I will make a PR for this. We should ask @kaeldai to review the PR once it's ready.