[SPARK-2516] Partial implementation of suggested changes - more to come
[SPARK-2516] Added exception handling around all file IO.
[SPARK-2516] Moved default values from a properties file in the classpath to a Map in SparkSubmitArguments
[SPARK-2516] Changed string literal naming convention from Scala standard to c standard based on feedback
[SPARK-2516] SparkSubmitDriverBootStrapper now takes care of its own property file loading
[SPARK-2516] Streamlined those functions that use exception handling
[SPARK-2516] All tests pass. Refactored launch environment creation function
[SPARK-2516] Moved utility methods to Utils module
[SPARK-3620] Added additional unit tests to improve test coverage