WebUI: Return full path to files

It's otherwise impossible to know the structure of a torrent.

src/webui/btjson.cpp

@@ -479,7 +479,7 @@ QByteArray btjson::getFilesForTorrent(const QString& hash)
         h.file_progress(fp);
         for (int i = 0; i < h.num_files(); ++i) {
             QVariantMap file_dict;
-            QString fileName = h.filename_at(i);
+            QString fileName = h.filepath_at(i);
             if (fileName.endsWith(".!qB", Qt::CaseInsensitive))
                 fileName.chop(4);
             file_dict[KEY_FILE_NAME] = fsutils::toNativePath(fileName);