GEOMESA-215 GeoMesa query should be exclusive of temporal filter date bo...

...unds for BEGIN, AFTER

* Partitions temporal predicates out and passes them to the STII/AIFI/IndexIterator.
* Adds special handling for DWithin.  (More special cases will be produced as we move away from FilterToAccumulo.)
Thanks to Hunter Provyn for providing the unit tests in FeatureWritersTest.scala.
"Yes".  I don't like it... from the BNF at http://docs.codehaus.org/display/GEOTOOLS/ECQL+Parser+Design
<relgeoop name> ::= "DWITHIN" | "BEYOND"
<relgeoop argument list> ::= "(" <expression> "," <expression> "," <tolerance> ")"
<distance units> ::= = "feet" | "meters" | "statute miles" | "nautical miles" | "kilometers"