CDK-796: Use CLI conf as DefaultConfiguration.
Merge pull request #263 from rdblue/CDK-796-cli-set-default-conf

CDK-796: Use CLI conf as DefaultConfiguration.
CDK-767: Add null default value to nullable CSV fields.
CDK-761: Fix inferred schema data samples.

This truncates values to 50 characters and removes all but a white list
of printable characters. Unicode characters will be replaced with '.' in
sample data for compatibility with the Hive MetaStore.