Add data from Collard et al. 2006

[joeroe]

This paper lists 21 cultural data sets used for phylogenetic analysis (Table 2). Some I've opened issues for with the original publications, others are harder to track down. The data isn't actually included with the paper, but the authors say "copies of the NEXUS files will be made available on request", so it might be worth investigating?

• Collard, M., Shennan, S.J., Tehrani, J.J., 2006. Branching, blending, and the evolution of cultural similarities and differences among human populations. Evol. Hum. Behav. 27, 169–184. https://doi.org/10.1016/j.evolhumbehav.2005.07.003