Use WeakHashMap for FlowStateMap
Only touch the flowMap once on read
Merge pull request #745 from twitter/fix-flowdef

Use WeakHashMap for FlowStateMap
Add .filter to KeyedListLike
add filterKeys
make sure to push filterKeys mapside
Use thread context classloader so that com.twitter.scalding.Tool can be used without fat jars
Merge pull request #752 from themodernlife/develop

Use thread context classloader when creating Jobs via reflection
Update serliazer to use the same class loading logic
Merge pull request #753 from themodernlife/develop

Make sure Kryo instantiator uses the thread context class loader
Re-add mapValues to IdentityReduce
Merge pull request #754 from twitter/mapValues-grouped

Re-add mapValues to IdentityReduce
Fix typo
Merge pull request #748 from twitter/filterMethods

Add .filter to KeyedListLike