Federate handles GET /federate.

NewV1Handler creates a http.Handler that serves the Maia v1 API.It also returns the VersionData for this API version which is needed for theversion advertisement on "GET /".

ReturnJSON is a convenience function for HTTP handlers returning JSON data.The `code` argument specifies the HTTP Response code, usually 200.

ReturnPromError produces a Prometheus error Response with HTTP Status code.

ReturnResponse basically forwards a received Response.

Server initializes and starts the API server, hooking it up to the API router.

VersionData is used by version advertisement handlers.