Added additional check in Validator->validateAccepted() to account for (int) 0 values.  (int) 0 values will no longer validate with this method.
Updated unit test to assert validation failure when (int) 0 value is evaluated.
Merge pull request #2883 from ryanrobertsname/bugfix-Validator-validateAccepted

Update to Validator->validateAccepted(), accounts for (int) 0 values ensuring that they do not validate