Some major changes to the fundamental code that calculates the turnover metric and put it into `analogue_function.R`:

1. Both climate and pollen run on the same function.
2. The same function runs both self and landscape metrics.
3.  The same function also looks forward and backward.
4.  This function is now parallelized so that it can run `parallel=TRUE` in `ddply`.

Awesome.

Also started moving `data` into `input` and `output` folders so that we know which ones are static and which can be re-written.