Schema 790

I know this is copied, but be on the lookout for logging statements like this.  It's log level debug, which means it will almost never get used, but it's doing a lot of work that always has to get done.  Things like string concatenation, calling methods, etc.  It is much faster, and functionally equivalent (as long as the .toString is good on the object being logged, which in this case it is), to do write this as:

`LOG.debug("Deleting HBase column {}", hbaseColumnName);`

In slf4j logging statements, `{}` is a placeholder for an object, printf style.