JsonLine should handle empty lines
Currently it fails while parsing
add scalding-hraven module, hRaven-based reducer estimation
add missing hbase dependency
don't double-define Config params, clean up imports, comments
Merge branch 'develop' into bholt/hraven-reducer-estimator
run hraven tests on travis (if we end up having any)
get api hostname from config, other minor changes from feedback
refactor into generic HistoryService/RatioBasedReducer and HRavenHistoryService
add hRaven client config params, some comments
make 'fetchPastJobDetails' return 'Try'
Merge branch 'develop' into bholt/hraven-reducer-estimator
make ReducerEstimator a monoid
Default behaviour is now to keep failing on empty lines, thus preserving previous behavior
Merge branch 'develop' of https://github.com/twitter/scalding into develop

Conflicts:
	scalding-json/src/main/scala/com/twitter/scalding/JsonLine.scala
	scalding-json/src/test/scala/com/twitter/scalding/JsonLineTest.scala
use thread classloader, remove fallback estimator, conditionally set flow step strategy
use 'Config.addReducerEstimator' in test
catch possible IOException when fetching flows
fix compile error in estimator instantiation
allow fetching multiple history entries
Add comments for memory-related reduce operations.