Inhibit sleep regardless of activity

"Active torrents" is a somewhat unintuitive concept as a basis for
preventing sleep, as torrents can become active or inactive on the
network at any time. This brings some predictability to the inhibit
sleep option, and will inhibit sleep as long as there are unpaused
downloads or uploads, regardless of network activity.

Closes #1696, #4592, #4655, #7019, #7159, #7452

src/base/bittorrent/session.h

@@ -454,6 +454,7 @@ namespace BitTorrent
         TorrentStatusReport torrentStatusReport() const;
         bool hasActiveTorrents() const;
         bool hasUnfinishedTorrents() const;
+        bool hasRunningSeed() const;
         const SessionStatus &status() const;
         const CacheStatus &cacheStatus() const;
         quint64 getAlltimeDL() const;