GEOMESA-232 Fixing CoverageReader, also upgrades to geotools 11.2 and scala 2.10.4
GEOMESA-199 Update our POM to support releases to LocationTech's Nexus instance
GEOMESA-240 Re-enable explainQuery

* The explainQuery function was disabled. This pr adds back an explainQuery function to the
 AccumuloFeatureReader class.
* Additional planning time information has been added.

An archetypal invocation now looks like

import org.geotools.data._
import geomesa.core.filter.TestFilters._
import org.geotools.filter.text.ecql.ECQL

val aparams = Map(
  "instanceId" -> "INSTANCE_ID",
   "zookeepers" -> "ZOOKEEPERS",
   "user" -> "USERNAME",
   "password"-> new String("PASSWORD"),
   "auths"-> "AUTHS",
   "tableName"-> "TABLE_NAME",
   "useMapReduce" -> "false")

val ds = DataStoreFinder.getDataStore(aparams)

val q = new Query()
val t = Transaction.AUTO_COMMIT
q.setTypeName("gdelt")

val afr = ds.getFeatureReader(q, t).asInstanceOf[AccumuloFeatureReader]

afr.explainQuery(q)

val fs = "INTERSECTS(geom, POLYGON ((41 28, 42 28, 42 29, 41 29, 41 28)))"
val f = ECQL.toFilter(fs)
q.setFilter(f)

afr.explainQuery(q)
GEOMESA-236 GeoServer Accumulo Coverage Store password should be hidden
GEOMESA-239 Change dependencies for Eclipse IP
GEOMESA-237 Convert AvroSimpleFeature to WKB

* Use WKB (Well Known Binary) instead of WKT (Well Known Text) for AvroSimpleFeature
* Results in 20x speedup on serialization/deserialization
Add a test for GeoHashSpiral.
Some fixes to the GeoHashSpiral.
GEOMESA-238 Users should be able to use Spark on GeoMesa data

* Added utility methods for initializing a Spark RDD on data stored in GeoMesa.
Fixed some bugs in GeoHashSpiral.
Now can prevent GeoHashes from being added multiple times.
KNN search is working, and the SearchProcessTest is complete.
Code cleanup.
A few wording changes.
More formatting changes.
Merge branch 'accumulo1.5.x/1.x' of github.com:locationtech/geomesa into wip_knn_search3
GEOMESA-241 refactoring geo pages for new table layouts, adding attribute index page
GEOMESA-250 ExplainQuery can be cut short.

There seem to be two problems:
* The variable 'cur' in CloseableIterator needs to be set upfront.
* Naming the 'bind' in CloseableIterator flatMap causes confusion between the compiler and the developer.
new inmplementation of bounded priorityQueue.
GEOMESA-253 closing shapefile datastores after use in GeneralShapefileIngest