PluXml 5.8.4

[+] Disable removing short words on urlify (P3ter)
FIX Icon's CSS in medias manager (P3ter)
FIX Reduce notification bar width (P3ter)
FIX Error "Constant PLX_SITE_LANG already defined" (bazooka07)
FIX Do not use urlify for links (P3ter)
FIX Medias sorting in the backoffice (P3ter, sudwebdesign)
FIX Medias breadcrumb in the backoffice (P3ter, sudwebdesign)
FIX 404 error with tracking params in the URL (bazooka07)
FIX Display thumbnail in administration for SVG medias #482 #479 (bazooka07)