Add a format output flag to ./accumulo ec-admin to support easy parsing.

[ddanielr]

Is your feature request related to a problem? Please describe.
When ec-admin is printing compaction details the external compaction ID and details regarding that compaction are split across two separate lines.

This is great for readability, but makes parsing this information difficult.

Describe the solution you'd like
Add a format option that allows the user to specify a delimited format for the message that is easy to parse programmatically (csv, json, etc).