WIP: Check if zone have enterprise plan enabled
If cloudflare account have free websites, it will break cloudflare exporter.
{"caller":"cloudflare_exporter.go:100","error":"graphql: zone 'ZONE_WITH_FREE_WEBSITE' does not have access to the path","level":"info","ts":"2020-02-20T18:07:49.760Z"}
This PR should fix it.