MGASA-2017-0429 Updated mediawiki packages fix security vulnerabilities

XSS when $wgShowExceptionDetails = false and browser sends non-standard url escaping CVE-2017-8808. Reflected File Download from api.php CVE-2017-8809. On private wikis, login form shouldn't distinguish between login failure due to bad username and bad password CVE-2017-8810. It's possible to...