GEOMESA 320, use apache commons csv

* replaced usage of javacsv with 1.0 release of apache commons csv in geomesa-tools
* updated test to ensure wkt still works with commons csv
* updated pom
GEOMESA-330 Avro SimpleFeature's getProperty should return a Property even when the value is null

This addresses an issue found by a user who was attempting to run the Quick Start tutorial.
GEOMESA-328 Fix IndexIterator exception
 * The fix is from @anthony-ccri.
 * The tests show the exceptions which we observed on tablet servers.
GEOMESA-334, 335 Add zookeepers, instance name and Separate Export from FeaturesTools

zookeepers and instance-name can be added to any command line argument. This is useful for cases where instanceName and zookeepers
cannot automatically be found. Additionally, auths and visibilities have been added to all commands. Finally, Export has been separated
out of FeaturesTools and Tools to add more flexibility in Export.
changing hadoop_conf to hadoop_conf_dir
addressing comments
adding more commands to the geomesa-test-script and adding a confirmation prompt to delete command
Merge branch 'fcr_instancename_zookeepers_params' of github.com:jdk2pq/geomesa into hadoop2.0withdcm-merge

Conflicts:
	README.md
	geomesa-core/src/main/scala/org/locationtech/geomesa/core/index/STIdxStrategy.scala
	geomesa-tools/bin/geomesa