[FLINK-1239] [streaming] IterateExample fix and parallelism setting in StreamExecutionEnvironment made public

Conflicts:
	flink-addons/flink-streaming/flink-streaming-examples/src/main/java/org/apache/flink/streaming/examples/iteration/IterateExample.java
[FLINK-1233] Fix flaky AggregateITCase
[docs] Add description of Quasiquotes compiler plugin in Eclipse to FAQ
[FLINK-1242] Fix streaming-examples and scala-examples POMs to work properly with Eclipse
[FLINK-1008] Fix createProgramPlan() throws exception

Problem was, that ExecutionEnvironment#getExecutionPlan clears the data
sinks, i.e. a following ExecutionEnvironment#execute will throw an error
because there are no data sinks.

This introduces a new flag for ExecutionEnvironment#createProgramPlan to
indicate, that the the sinks shall not be cleared.
This does not break any existing code.

This closes #184
[FLINK-890] [docs] Adjust examples to show reader methods and correct class-vs.-interface errors.
[FLINK-1244] setCombinable() returns operator

This closes #205
[FLINK-1172] [docs] Fix broken links in documentation

This closes #206
Fix flaky test SumMinMaxITCase
[FLINK-1246] Add additional debug output to flaky recovery test
[tests] Various stability fixes to tests
[build] Manage version of joda-time to prevent conflicts between dependencies.
[FLINK-1207] Context environments are realized through factories
  - local execution blocking is reset after each run
[FLINK-1237] Add support for custom partitioners
  - Functions: GroupReduce, Reduce, Aggregate on UnsortedGrouping, SortedGrouping,
               Join (Java API & Scala API)
  - Manual partition on DataSet (Java API & Scala API)
  - Distinct operations provide semantic properties for preservation of distinctified fields
  - Tests for pushown (or not pushdown) of custom partitionings and forced rebalancing
  - Tests for GlobalProperties matching of partitionings
  - Caching of generated requested data properties for unary operators

This closes #207
[bin] Remove MaxPermSize parameter for JVM 1.8

This closes #200.
[FLINK-1209] [compiler] Improve error messages when forgetting to close an iteration
[FLINK-1250] [config] [docs] Correct and document config keys for heartbeat intervals and timeouts

This closes #212
[FLINK-1247] [docs] Fix broken links in documentation

This closes #213.
Minor code clean up to get rid of IntelliJ IDEA warnings

This closes #214.
Add byte array serialization to InstantiationUtil