Fix false positive malware report at Emsisoft

Via an incoming email we learnt that the server from where the MuseScore msi is served is false positively identified as a malware site: https://www.virustotal.com/en/url/33abde1f3e56aeb07258ff746b7ad75bc817f…

To get this fixed, we submitted a report at Emsisoft: http://support.emsisoft.com/topic/17236-false;positive-report/