Update Pango color ordering

This commit took nested ordering of Pango lineages from https://github.com/cov-lineages/lineages-website/blob/master/_data/lineage_data.full.json and used this to update color ordering for "pango_lineage" as well as creating a color ordering for "Nextclade_pango". Previously, "Nextclade_pango" had random colors per lineage. This will now generally give adjacent Pango lineages similar colors.