remove usage of immutablemap in systembolt.
it was causing kryo deserialization issues because immutablemap is not
registered with kryo.
Merge pull request #564 from jasonjckn/0.9.0

remove usage of immutablemap in systembolt.
Ignore NoNodeExists exceptions
Refactoring: Added helper function exceptionCauseIsInstanceOf
Merge pull request #566 from jasonjckn/0.9.0-nonodeexists

Ignore NoNodeExists exceptions
Merge branch '0.9.0'
Merge branch '0.9.0'
Clean up Mesos dist.
Build fix.