Functionality to run ScanConsistencyIT standalone

[kevinrr888]

Closes #3646. Refactored ScanConsistencyIT to be able to be run standalone. Can now be run as a test or from main.

[kevinrr888]

Added requested changes:

• Removed "@ throws Exception" from javadoc. Hopefully fixes build failure from "Checkstyle violations".
• Shutdown the executor in a finally block
• Table is now deleted when test is done
• Check args length using Preconditions.checkArgument()
• Moved client into try-with-resources block
• Messages are now logged in debug mode if in testing context, info mode otherwise

[dlmarion]

The same can be achieved using the instructions here. Just curious, why would we need this?

[keith-turner]

The same can be achieved using the instructions here. Just curious, why would we need this?

We may not, I had forgotten about that, wonder if the following work

1. Setup accumulo in uno
2. copy test jar to uno lib dir, this is needed because the test has server side code it runs
3. restart accumulo
4. run test using mvn passing in uno accumulo props file

If it does work may still want some of the changes in this PR like deleting the table.

[keith-turner]

When running this test manually against an existing instance, would like to be able to adjust this sleep. Would like to be able to run this test against an uno instance for hours.

[dlmarion]

See this for running an IT against an existing instance. Caveat: I've never tried it.

[kevinrr888]

More requested changes:

• Table deletion is no longer in finally block
• Use log.info
• Main now accepts sleep time

Since we should be taking in a sleep time parameter, not sure how this would be done using mvn.

Let me know if the approach using main is sufficient.