GEOMESA-273 Id queries do not work

Intercept ID queries and go straight to the
record table
GEOMESA-277 Refining DensityIterator Stacking

* Refactored the DensityIterator to be separate from the SFFI.
* Moved the DensityIterator to run after the SFFI.
Merge branch 'accumulo1.4/1.x' into fcr_min_geodetic_dist_to_gh_1.4