Store advisoryHostFQDNs data in config.mongos collections

When OpsManager is monitoring router (mongos) processes that it did not provision itself, it relies on the contents of the config.mongos collection on the config servers to enumerate all of the mongos processes. This ticket is to have the router processes include the information they provide in the advisoryHostFQDNs field of their serverStatus command responses when they self-report their identities by writing to config.mongos.

In addition to the other fields in a config.mongos document, mongos servers should add an advisoryHostFQDNs section identical to the one reported in serverStatus, to facilitate discovery by the OpsManager monitoring service.

– original description –
For Cloud and Ops Manager autodiscovery purposes, when SSL is enabled, the config server collection "config.mongoS" and rs.status() should expose FQDNs instead or in addition of short hostnames.

This is a followup for the now closed ticket SERVER-2421 that added FQDNs to the serverStatus function. That is not sufficient since when using SSL you are not allowed to connect and get the serverStatus.advisoryHostFQDNs output using the shortname (hostname validation will fail).