Use truncated torrent hash in temp path

src/base/bittorrent/infohash.cpp

@@ -68,7 +68,6 @@ bool InfoHash::isValid() const
     return m_valid;
 }
 
-
 InfoHash::operator libtorrent::sha1_hash() const
 {
     return m_nativeHash;

src/base/bittorrent/session.cpp

@@ -333,7 +333,9 @@ QString Session::tempPath() const
 
 QString Session::torrentTempPath(const InfoHash &hash) const
 {
-    return m_tempPath + QString(hash) + "/";
+    return m_tempPath
+            + static_cast<QString>(hash).left(7)
+            + "/";
 }
 
 bool Session::isValidCategoryName(const QString &name)