upgraded to ElasticSearch v0.20.4

fixes #SERVER-276
start AMQPSyncInitializer on non-master nodes too

fixes #SERVER-278 (i hope)
AMQP queues are no longer auto-delete

fixes #SERVER-279
Processor was not writing batches to all outputs

fixes #SERVER-271
bumped version to 0.10.0-rc.4
requeue messages if buffer is full

fixes #SERVER-283
no longer requiring rule regex to fully match

fixes #SERVER-284
retry master detection after stale timeout

fixes #SERVER-281