add locales array to /calendars path response

[JohnRDOrazio]

There is currently no way to know which locales are supported for the General Roman Calendar.

A frontend UI with option inputs to assist in formulating a request to the API has no way of listing available locales to send in the request.

We should add a locales property to the metadata (/calendars) response so that a frontend select can list currently supported locales.

[JohnRDOrazio]

Fixed in commits https://github.com/Liturgical-Calendar/LiturgicalCalendarAPI/compare/1b1d0861a024e9c6e9b3ab06dd1c73ff4b454a61..d8a58cab7a11e23d5931583b6b15f517ff516640