[MixCloudBridge] Fix bridge broken after DOM changed
[MixCloudBridge] Fix bridge broken after DOM changed

This commit fixes DOM changes reported via #436
New DOM introduced via
https://blog.mixcloud.com/2017/01/10/take-a-look-at-the-new-and-improved-mixcloud/

teromene/rss-bridge,ORelio/rss-bridge,GregThib/rss-bridge,simonbru/rss-bridge,mro/rss-bridge,simonbru/rss-bridge,Frenzie/rss-bridge,RSS-Bridge/rss-bridge,RSS-Bridge/rss-bridge,kranack/rss-bridge,RSS-Bridge/rss-bridge,kranack/rss-bridge,mro/rss-bridge,kranack/rss-bridge,Frenzie/rss-bridge,LogMANOriginal/rss-bridge,kranack/rss-bridge,Riduidel/rss-bridge,ORelio/rss-bridge,sebsauvage/rss-bridge,LogMANOriginal/rss-bridge,teromene/rss-bridge,Riduidel/rss-bridge,Riduidel/rss-bridge,ORelio/rss-bridge