[FLINK-917] Rename netty IO thread count parameters
[FLINK-934] Remove default values for JobManager and TaskManager JVM heap sizes in startup scripts
Implement AvroOutputFormat
Add method to pass a schema for AvroOutputFormat
Aggregators and convergence criteria as objects instead of classes
[YARN] Improved the check for resource availability within the cluster
Minor fix for displayed estimates.
[FLINK-935] Fix compiler logic that pushed work out of the iteration loop.
Made FieldSet and FieldList immutable collections to prevent bugs to to side effect mutations
Made LocalProperties Immutable (avoid side effect mutation bugs)
Change several Iterators to Iterables in the compiler (simpler code)
[FLINK-935] (continued) Correct feedback property check for iterative algorithms.