[Kinotify] "High" handling priority.
[Core] Changed EntityTestHandleResult::CancelOthers_ semantics.

Now it aborts handling by other plugins that have lower entity test handle
priority results. Same-and higher-level plugins still get a chance to
handle the entity.
[DeadLyrics] Fixed Qt 5.4 build.
[Liznoo] Find QtConcurrent.
[Liznoo] Added missing include.
[Blogique Metida] Fixed Qt 5.4 compilation.
[Interfaces] Removed unneeded QList<QModelIndex> metatyping.
[Interfaces] Fixed IJobHolder Qt 5 compatibility.