Disable the 'prune' filter spec because the test should have always failed, but it didn't, and I'm not sure what to do next...
Style improvements; alsos kip the event if it doesn't have the given source field
event v1
A recent change to the test_utils.rb made filter yields appear earlier than the 'return' event, so updating the clone test to acknowledge the order change
Merge git://github.com/logstash/logstash