CDK-384: Add show records and csv import commands.
CDK-384: Add CSV import test.

This also allows access to PathIterator and SchemaValidationUtil in
spi.filesystem to allow more checks (like apparent schema compatibility)
to the CSV import process.
CDK-384: Fix dataset help help.
CDK-384: Don't print default for arity-0 args.
CDK-384: Use "hive" instead of "hcatalog".
CDK-384: Remove unnecessary Configuration in show.
CDK-384: Update minimize docs and fix CSV examples.