ERK style repair fails

The ERK now fails to a blank screen when it attempts to run the style repair. This is because of the fix for this ticket.

We are now suppressing the "Non-static method utf_normalizer::nfkc() should not be called statically" error message. This error is being triggered in the style repair when we call utf8_clean_string() in /stk/includes/critical_repair/autorun/style_dir_repair.php (line 83). Instead of displaying the message, everything aborts silently.