Added support for acknowledgement from other nodes in open/close index api

The open/close index api now waits for an acknowledgement from all the other nodes before returning its response, till the timeout (configurable, default 10 secs) expires. The returned acknowledged flag reflects whether the cluster state change was acknowledged by all the nodes or the timeout expired before.

Closes #3400
Updated test to reflect added acknowledgement from all nodes in open/close index api

If it's acknowledged all the other nodes already hold the latest cluster state, thus we can search on the closed index and be sure we get an error back
Renamed MetaDataStateIndexService to MetaDataIndexStateService for consistency