Add note about Message Processors Configuration order

[dotsam]

Running Graylog 2.3.0+81f8228, the default Message Processors Configuration order is:

1. GeoIP Resolver
2. Pipeline Processor
3. Message Filter Chain

Documentation at http://docs.graylog.org/en/2.3/pages/pipelines/usage.html#configure-the-message-processor and http://docs.graylog.org/en/2.3/pages/pipelines/stream_connections.html#the-all-messages-stream notes that the message filter chain needs to run before the pipeline processor to connect pipelines into a stream besides the "All messages" stream.

Can a note be added to this config example that mentions that?

[RedVortex]

That was exactly my issue. I worked on the regex for hours before finding you comment about why, even though my regex was valid, the message wasn't updated and parsed properly. Thanks !