Keep the pre-mutated producer graph around for debug info
Fixes final flat mapper interaction with cache
More logging
Merge pull request #381 from twitter/feature_fix_FFM

Feature fix ffm
Merge branch 'develop' of github.com:twitter/summingbird into await-cleanup

Conflicts:
	summingbird-storm/src/main/scala/com/twitter/summingbird/storm/StormPlatform.scala