Fix bug in MergeableSelector

Fixes #168

Change-Id: If55ba9772e4fb12037c16960ddb1ed085f695a8e
Reviewed-on: http://gerrit.causes.com/38074
Tested-by: jenkins <jenkins@causes.com>
Reviewed-by: Shane da Silva <shane@causes.com>
Add spec for MergeableSelector fix

Change-Id: Id3930fdaeeb799713b95f4e0b962bf4426f0c4e6
Reviewed-on: http://gerrit.causes.com/38075
Tested-by: jenkins <jenkins@causes.com>
Reviewed-by: Shane da Silva <shane@causes.com>
Reword changelog for MergeableSelector fix

Changelog entries should give a good high-level overview of what the
problem was without the reader having to open additional links for
context.

Change-Id: Ie9e2b98021b0f6979d4affd2d6f8ffbc4faa5090
Reviewed-on: http://gerrit.causes.com/38076
Tested-by: jenkins <jenkins@causes.com>
Reviewed-by: Shane da Silva <shane@causes.com>