Spike: Focus on destinations rather than travel paths

_Not sure if this is a good idea_

Since [Co₂ordinate](https://github.com/developmentseed/co2ordinate#coordinate) focuses on destinations for people to meet, the design of the tool could be rethought to focus more on destinations instead of travel paths.

If destinations are the focus, we could display or filter based on other data, such as how "sustainable" a city is, its ability to host conferences or remote workers, etc.