GEOMESA-223 Fixing delete of non-existing entries
GEOMESA-221 Create encoding for SFTs that includes index toggle

Added a utility class for working with SimpleFeatureTypes.
Toggleable secondary indexes
Upgraded specs2.
GEOMESA-228 Remove unstable tests

* Removed tests in FilterTester.scala from the build.
 Those tests were failing in somewhat arbitrary and non-reproducible ways.
GEOMESA-57 Adding default constructor for TimestampSetIterator and test (originally from @cne1x)
GEOMESA-209 - Identifying unique GeoHash sub-strings in a polygon is both slow and inaccurate

Added a few new unit tests, re-wrote the way we compute these
GeoHash sub-strings, and added a few utility methods to the
RectangleGeoHashIterator and the GeoHash.
GEOMESA-231 Allow longs in SimpleFeatureTypes
GEOMESA-191 Implement deleteSchema for featureType

deleteSchema removes both metadata and the 3 tables per feature type. Also
checks to see whether or not it's an older 0.10.x table, and if so, uses
the AccumuloFeatureWriter's remove() function to remove rows from the table.