Patch to find qt5 plugins.

Patch by Marius Brehler <marbre@linux.sungazer.de>
--- a/bin/mendeleydesktop
+++ b/bin/mendeleydesktop
@@ -75,7 +83,7 @@ def get_paths():
         else:
             results['MENDELEY_BIN'] = results['MENDELEY_BASE'] + "/lib/mendeleydesktop/libexec/mendeleydesktop.i486"
 
-        results['MENDELEY_BUNDLED_QT_PLUGIN'] = results['MENDELEY_BASE'] + "/lib/mendeleydesktop/plugins/"
+        results['MENDELEY_BUNDLED_QT_PLUGIN'] = "/usr/lib/qt5/plugins"
 
     # Path to Mendeley Desktop and PDFNet libraries
     results['MENDELEY_LIB'] = results['MENDELEY_BASE'] + "/lib/"