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
I think we tend to use "properties" when we have some general property of the data type to test (e.g. quickcheck prop), and spec or test when we are just writing ad-hoc unit tests.