Locus elements for running headers should be inside the tei:fw element

[wlpotter]

Since the tei:fw element permits a child locus, if Wright indicates exemplar loci for that header, the locus element should be within the fw not outside it.

Consolidated schema does not mention folio locations; our guidelines don't yet either.

Will likely require a simple xquery update to do this.

Also adding documentation label since we will need to add to our guidelines