Avoid querying local dc with prepared query

Prepared query is a great mechanism.

It will be very likely that the DC list will follow the precedence of which DC to query.
Right now the local DC you execute the query from has an higher priority than the DC list inside the prepared query.
The suggestion is to add "skip the local datacenter" attribute with a true/false value to prepared query (json format).
https://www.consul.io/api/query.html#sample-payload

This request discussed also in consul google group, @slackpad suggested to create a feature request.
https://groups.google.com/forum/#!topic/consul-tool/O-JWve5uN0E