From: Frazer Clement <frazer.clement@oracle.com>

- Add a new 'NoWait' operation option for locking PK reads
- Reads with this option enabled will immediately return with an
  error should it detect that the row is already incompatibly locked
  by a different transaction

Change-Id: I4130a6688e83a2b12b7e00c9e0cf1ee6c208404d