Handle redirects for EXID types

[tychonievich]

From FamilySearch/GEDCOM#122, we had this suggestion:

Example:
https://gedcom.io/exid-type/FamilySearch-PersonId/ABCD-123 should invoke a script that redirects everything underneath https://gedcom.io/exid-type/FamilySearch-PersonId/ where that one might redirect initially to, say, https://familysearch.org/platform/tree/persons/ABCD-123

Jimmy reports we should look at: https://superdevresources.com/redirects-jekyll-github-pages/