GEOMESA-494 GEOMESA-523 GEOMESA-525 Replace scopt with jcommander

* Replaced scopt with jCommander
* Refactored arguments into common classes
* logged to stderr instead of stdout to support redirecting of ouput (removed stdout flag) (GEOMESA-523)
* added "json" in addition to "geojson format"
* updated readme
* Bundled SLF4j with assembly (GEOMESA-525)
To clarify, if the date field is not additionally indexed, then Time-Index shows up; otherwise, both (Time-Index) (Indexed) is printed?  Is that right?  (I'm wondering if the fizz-buzz case requires explanation.)