[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
Added getExecutionEnvironment to the DataSet of the Scala API.
[FLINK-1254] [compiler] Fix compiler bug for pipeline breaker placement

This closes #216
[FLINK-1253] [tests] Make sure tests do not die with garbage collection overhead exceeded

This closes #217