[uTorrent] Guarantee a folder

uTorrent does not create a folder in case only one file is present in
the torrent. This is a workaround that detects torrents with one file.
It then removes the torrent and readds it with a specified subfolder.
Trailers not downloading. fix #1563
Only backup database max once an hour. fix #1218
Better year guessing. fix #609
Create db backup dir before trying to use it. fix #2207
Don't try to finish an already closed connection
Try the info dict to get title. fix #2206
ASCII encode md5 string. closes #2167
Merge pull request #2163 from mano3m/develop_utorrent

Fix folder issue uTorrent
Different seperator for folder and filename
Merge remote-tracking branch 'upstream/develop' into develop