Remove backticks from smarty - smartyv3 compliance
Created by: eileenmcnaughton
This ensures the extension will still work on sites that use Smarty3 rather than Smarty2 (which hopefully will be all before too long)
This would go with tagging a release 3.5.3. Note the version compatibility update came from civix - but anyone who wanted to run on an older version could just run an earlier version of this extension & not get the smarty3 support (which they would not get anyway)