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
[streaming] Source parallelism API update

The new preferred way is calling setParallelism() after adding the SourceFounction. This solution works any other operator.
[streaming] Fixed async buffer sending at end of AbstractInvokable