Examples and Tests for Sqoop Execution

1) Included examples for both Sqoop Export and Import with Execution
2) Added tests for the examples
3) Added tests for the SqoopExecution trait especially for the failure scenarios
@stephanh ParlourDsl exposes 'update' method stores SqoopOptions => Unit function given as parameter. Using this method we can eventually call every method on SqoopOptions.