GEOMESA-122 Split OR filters into multiple queries

* Created a OrSplittingFilter Visitor which helps break apart a more complex Filter into pieces.
* Moved up the SelfClosingBatchScanner into core and implemented a basic CloseableIterator trait.
GEOMESA-131 Implemented get properties methods in AvroSimpleFeature

Tests included in AvroSimpleFeatureTest.scala
GEOMESA-149 Update GeoServer deployment instructions

* Includes commons-codec jar.
GEOMESA-133 SimpleFeature UserData lost in IndexQueryPlanner

Add functions to transfer the SimpleFeatureType UserData into and out of IteratorSettings, which would otherwise be lost
when passed to the Iterators via DataUtilities.encodeType
GEOMESA-151 allowing schema to not be set in datastore config for already created features
GEOMESA-155 fix for non-thread-safe map

Changed attributeNameLookUp into a HashMap with SynchronizedMap traits
Merge branch 'accumulo1.5.x/1.x' of github.com:locationtech/geomesa into f_set_default_dtg
Now SF_PROPERTY_START_TIME is set to the first date/time attribute found in the SimpleFeatureType, without regard to the total number of
such attributes found.