Fix name of runIndexingJob method
Add row and timestamp scan parameters

Allow setting the start and end rows for the scan used for
indexing, as well as the start and end timestamps for cells to be
included in indexing.
Add initial MR index integration test structure
Extract argument validation/evaluation from tool

Separate out the evaluation of various combinations of cmdline
arguments into a separate class to allow for easier isolated
testing of various combinations and their effects.