XWIKI-7514: Upgrade to Groovy 1.8.6
XWIKI-7514: Upgrade to Groovy 1.8.6

pbondoer/xwiki-platform,xwiki/xwiki-platform,pbondoer/xwiki-platform,xwiki/xwiki-platform,pbondoer/xwiki-platform,pbondoer/xwiki-platform,xwiki/xwiki-platform,xwiki/xwiki-platform,pbondoer/xwiki-platform,xwiki/xwiki-platform