GEOMESA-113 Change naming scheme to reflect Accumulo version
GEOMESA-109 Refactor IndexSchema

* Broke up the IndexSchema file into separate files.
* Changed the STII's use of an IndexSchema to a IndexEntryDecoder.
* Pushed everything down into the IndexQueryPlanner in preparation for work on it.
GEOMESA-111 Remove the AggregatingCombiner

* In order to remove the AggregatingCombiner, we needed a new 'Is this a data row?' signal.
GEOMESA-112 adding commons-vfs2
GEOMESA-102 filter-to-accumulo should handle ANDs and ORs

Simplistic addition that supports relativley simple
conjunction and disjunction.  Does NOT support negation.
Corrected ECQL syntax in documentation.
Extension for simplistic handling of NOT term.
Changes based on reviewer comments.
Additional changes motivated by reviewer comments.  Rebased against LT master.
Additional changes based on reviewer comments.