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.
[FLINK-942] Fix bug in config.sh to correctly set user-specified JVM args

This closes #22
[FLINK-930] Netty Initialization is sometimes very slow

This closes #19
Artificial commit to close pull requests.

This closes #5
This closes #6
This closes #10
This closes #12
This closes #14
Do not limit the client's heap space (See FLINK-934)

[ci skip]
This closes #18
Added Zihong Cao to CONTRIBUTORS list

[ci skip]
This closes #21