Changed the assignment of ecozones so that "Lakes" are not included as a division, and any sample that has an unassigned ecozone gets assigned the closest ecozone to it.  In most cases these re amples close to large bodies of water (added this in `data_cleaning.R`.

Added a new conceptual plot, I think it's better.  Also added a new dissimilarity metric, one is the closest self point, the other is the closest landscape point (excluding those from the core), and the last is a bootstrap value.

Will re-run to get a better plot.
Overnight run, re-ran `rep.frames`, now with absolute minimum, landscape minimum, site-level minimum and bootstrapped minimum.