Add monkey atlas to SANDS

[UlrikeS91]

I have received an offline request about the following atlas that a research has used in relation to a dataset:

G. Paxinos, X.F. Huang, and A.W. Toga (2000) "The Rhesus Monkey Brain in Stereotaxic Coordinates" (Academic Press)

In this case the regions of interest are V1 & V4, but this should not matter too much. We should consider adding it to our instances.

FYI @lzehl, @tgbugs and @MaaikevS

[UlrikeS91]

Some background stuff:

• https://ro.uow.edu.au/hbspapers/3613/
• https://www.researchgate.net/publication/247980150_The_Rhesus_Monkey_Brain_in_Stereotaxic_Coordinates (potentially able to get pdf?)