Ensure we don't send broken UTF8 data to the client.
This seems to prevent a PHP bug from being triggered.

Without hex-encoding of control characters, PHP is segfaulting on
numerous platforms with certain strings. Still working out the
exact string combinations that trigger this for reporting to PHP.
Another place to ignore SMS changes.
We no longer use loop counters.

Bug: 12707
BFN
Add migration to remove synckeycounter data.

Removes data erroneously added due to Bug: 12707