Get species for location / region

[dbradnum]

I recently helped a fellow eBirder answer a question about the total number of species seen at hotspots within a distance of his home. This involved a couple of eBird API functions that aren't yet included in rebird:

1. Get nearby hotspots
2. Get species list for a region

I've got R code up and running for both of these now, and am happy to tidy it up and submit as pull requests for the package - hopefully it'll be useful for other people.
I can see that #83 is already open for the first API call, so I'm raising this to cover the second one.

Hope this all sounds OK? Do let know if there's anything I should bear in mind, or I inadvertantly go astray with the fork > branch > pull request process!

[sebpardo]

I just noticed this issue. Turns out I already wrote a function ready that does both the ref/hotspot and ref/hotspot/geo API requests so I'll just upload it now. Would be neat to see how different (or similar) your approach was to mine.