Simplifications and logging updates

  * Replaced our own String <-> Stream converters with Apache Commons IO
  * Moved all object instantiation logs from loglevel INFO to FINE
  * Moved some more fine grained logs from INFO to FINE
Merge pull request #905 from Microsoft-CISL/weimer_cleanups

Simplifications and logging updates
Merged master
merged master
Some cleanup
fixing a typo
small changes in Broadcast demo settings
allreduce
Handle failures in allreduce
allreduce with new task addition and failed task deletion
update allreduce to merge code from shravan_groupcomm_interfaces
improve hyper cube topology control and fix bugs in handling source dead/add events
merge code from shravan_groupcomm_interfaces
fix comments
add logs
small modifications, commit for merging
allreduce on chunk messages through ReduceScatter+Allgather
refine client control flow
add version control and encode iteration and comm type info to bytes
merge code from shravan_groupcomm_interfaces