updated the sentry output and test cases to use the new protocol
buffer generated Message types
updated CEF output to use dot notation for nested dicts in msg.Field
added support for protobuf generated message type for statsd output
Merge branch 'master' into features/protocol-buffers

Conflicts:
	outputs.go
	sentry.go
	sentry_test.go
	statsd.go
	statsd_test.go