[SECURITY] Fedora 26 Update: roundcubemail-1.3.6-1.fc26

RoundCube Webmail is a browser-based multilingual IMAP client with an application-like user interface. It provides full functionality you expect from an e-mail client, including MIME support, address book, folder manipulation, message searching and spell checking. RoundCube Webmail is written in PHP and requires a database: MySQL, PostgreSQL and SQLite are known to work. The user interface is fully skinnable using XHTML and CSS 2.