Batch processing mapping updates can cause missed merged mappings when batching multiple types
when we bulk changes, we need to use the same index metadata builder across the tasks, otherwise we might remove mappings erroneously
 also, when we check if we can use a higher order mapping, we need to verify that its for the same mapping type
bulk response has errors indication + status per item
closes #4002
Invoke the DocumentType listeners *before* the mappers are updated. This fixes an issue where if two or more concurrent percolate index requests are processed, the first request would the `.percolator` type mapping, but the real time percolator listener wouldn't be active, this would result in that the subsequent concurrent requests wouldn't be parsed and kept in memory and would never be included in any percolate api result. This issue any occurred when `.percolator` type is created on the fly.

Also made the call to PercolatorQueriesRegistry#enableRealTimePercolator and #disableRealTimePercolator synchronized, so that for the same shard the RealTimePercolatorOperationListener can't registered twice.
Renamed the methods in DocumentListenerType to actually reflect when these are invoked.