Tweak to php-gettext stream reader; initialize local variable before appending data to it to avoid triggering an E_NOTICE message.

extlib/php-gettext/streams.php

@@ -108,6 +108,7 @@ class FileReader {
 
       // PHP 5.1.1 does not read more than 8192 bytes in one fread()
       // the discussions at PHP Bugs suggest it's the intended behaviour
+      $data = '';
       while ($bytes > 0) {
         $chunk  = fread($this->_fd, $bytes);
         $data  .= $chunk;