Remove duplicate utf8 encoding

[victorjonsson]

Calling utf8_encode in SolrPhpClient/Apache/Solr/Service.php on line 770 destroys multibyte characters.

Suggested change: (might also be good to add before calling htmlspecialchars on line 787 in the same file )

if( !seems_utf8($multivalue) )
  $multivalue = utf8_encode($multivalue);