WIP: GEOMESA: 72, 224, 225, command line tools

This is a work in progress PR (comments please) for the creation of a basic command line toolset for GeoMesa. This PR comprises three tickets: create a simple ingest tool to allow users to ingest a variety of GIS files (csv, tsv, shapefile, geojson, etc) into accumulo (geomesa-72),  exporting to csv and shapefiles (geomesa-224), and basic feature management (geomesa-225).  This PR serves as a foundation, to be improved on and expanded in function. 

at the moment all of this works to varying degrees, ingest not so much.
You shouldn't use 'asInstanceOf' unless you have a great reason.  Importing the implicit should be sufficient.