Curate standard geolocation rules

[joverlee521]

Originally part of #1003, but this is a much bigger task than just porting over an existing script!

We have a great list of manually curated geolocation rules in ncov-ingest that our pathogen-repo-guide points to as the "general" geolocation rules, but these should really be curated down to a standard set of geolocation rules in augur.

[victorlin]

Various repos are referencing https://raw.githubusercontent.com/nextstrain/ncov-ingest/master/source-data/gisaid_geoLocationRules.tsv directly. This makes it fragile to nextstrain/ncov-ingest#449 or any other renames. A couple things that could be done here without involving any curation work:

1. Copy the file into the Augur repo
2. Update references to use the file in Augur with - alias to the default branch