Build out a test suite

[davecharron]

Add tests for the following:

• Command line argument validation
  • No arguments
  • Invalid arguments
  • Missing required arguments
• Configuration
  • IBMiDotEnv credentials
  • Kafka broker URI
• Table resolution
  • Ordinary identifiers
  • Delimited identifiers
• LIST action
• ADD action
• REMOVE action
• GET action
• DAEMONSTART action