Cardinality aggregator

Move the event receiver firehose such that standalone realtime nodes can use it

Alpha-numeric sorting for topN

Smarter server selection at the broker level

Add more endpoints, fixes #517

Exclude old netty version from certain dependencies

add filesystem checks again

Use same logic for compression across creating files, reading from
files, and checking file existence

removing these checks breaks when there is no data for any interval

Fix FileNotFound in realtime nodes

protect check for hasSwapped.

Fix race in ingestion that can cause FNF,
Properly check for partitionNum
shutdown persistExecutor

update java-util

Small fixes to router

Reduce some bloat in the code base

Igal druid