Can set graph signal type for data graph vertex.
WIP Scalable eager convergence detection
WIP Test for new eager idle detection.

Still fails.
WIP Bugfixes

Async works fine, sync sometimes gets stuck after signal phase when
there are multiple nodes.
WIP eager idle detection.

Some debug code enabled.
WIP Eager idle detection.

Works, but should shield the coordinator even more.
WIP eager idle detection

Reduced the number of status messages that reach the coordinator.
Added Kryo init, tuned test params for Travis CI
Removed println statement in test.
Added Kryo binding.
Reduced test load for Travis.
Merge branch 'wolf-features'