Updated dataset to 13ca9a92d5b535681a52d550d9c49daa857c371c

I noticed that there's been quite a few updates to the [datacenters.csv](https://github.com/client9/ipcat/blob/master/datacenters.csv) since the last time [data/datacenters](https://github.com/kickstarter/ipcat-ruby/blob/master/data/datacenters) was updated, so I went ahead and regenerated the dataset from the latest version, which is [`13ca9a9`](https://github.com/client9/ipcat/commit/13ca9a92d5b535681a52d550d9c49daa857c371c)