Squashed commit of the following:

commit b60b5620938facb00725d06d173b875e1fce7f86
Author: Ariel Weisberg <aweisberg@voltdb.com>
Date:   Wed Oct 15 13:42:06 2014 -0400

    For ENG-6607, remove unused DummyUndoQuantum

commit 4f3f74073edb05eaa19437f127c133ad4c6aef2a
Author: Ariel Weisberg <aweisberg@voltdb.com>
Date:   Wed Oct 15 13:34:29 2014 -0400

    For ENG-6607, cleanup based on Paul's review comments

commit 69d1309e18a51a5d1d3c80996e2074c7a6be0bae
Author: Ariel Weisberg <aweisberg@voltdb.com>
Date:   Tue Sep 30 17:58:05 2014 -0400

    For ENG-6607, based on feedback clean up error message to be more professional/helpful

commit b06a3365e09b62b464cd4e16d569b1033066b14b
Author: Ariel Weisberg <aweisberg@voltdb.com>
Date:   Mon Sep 29 17:42:21 2014 -0400

    For ENG-6607, add a few more tests and add missing handling to DRIdempotencyFilter

commit 599aac5ddf55ff8055cc8b411300e559b647cdb7
Author: Ariel Weisberg <aweisberg@voltdb.com>
Date:   Mon Sep 29 16:18:38 2014 -0400

    For ENG-6607, add support for truncate table to DR2