Use the ICC as the basis for the initial `GeologicTimePeriod` records

[grantfitzsimmons]

When first creating a new *paleo or geology discipline, the GeologicTimePeriod table is populated with a chronostratigraphic chart that has no clear source.

Going forward, we would like to use the ICC from IUGS (see here for more information) as the basis for these tree records. We should use this as our new starting point and make sure to do the following:

If/when you do redistribute the Chart data, please could you:

preserve the identifiers for each time/strat unit, so Jurassic is http://resource.geosciml.org/classifier/ics/ischart/Jurassic
this allows linking back to the source-of-truth

preserve the colours used, as per the Colour Chart (Excel) and the colour markers in the data version of the Chart for consistency

We could preserve the HEX colors in a text field and use them for visualization sometime in the future if we would like.