Verbose option should probably be deprecated

Hi,

Data Validation Tool has a very good way of printing information to troubleshoot and debug and that is by using `-ll=DEBUG`. We also have the verbose option `-v`. It is sparingly used and is used primarily to print the queries. I suggest we deprecate this option and move all such usage to `logging.debug`. The code has some strange structure as follows:
```
if self.verbose:
logging.info(target_config)
```
If the user specified verbose `-v`, then the information is logged at the info level, otherwise it is not. Best to replace these with `logging.debug` and get rid of the `-v` or quietly change it to `-ll=DEBUG` under the covers.

Sundar Mudupalli