WalPrettyPrinter should include the table name

I was playing around with a large WAL file to debug something and I noticed a couple missing items.

• Pretty printer doesn't print the table name. It is difficult to map the region hashes to a table name manually.
• It should include an option to filter the edits by table so that we can only see the entries for a given table. A similar option exists for regions.

I hacked it locally, I thought this might save some time for others too if the fix goes into the master.