bump loggregator

3db20d0 Emit dropsonde log messages with correct timestamp
bdc607f Remove all /varz and /healthz bits from deaagent
a36ae68 Allow LoggingStream.Close to interrupt a Read
666741a Whitespace
5b865c8 Update metron_agent/spec

Signed-off-by: John Tuley <jtuley@pivotal.io>