Update iptorrents.py

Adds another URL parameter when searching on iptorrents for brrip.  This allows it to find brrip that are also classified as 720p/1080p.

See this thread for info:
https://couchpota.to/forum/viewtopic.php?f=5&t=4032&sid=7892abbaaca9dad8bd3cc27cafb7fd33

And this prior pull request for more info:
https://github.com/RuudBurger/CouchPotatoServer/pull/3696
Merge pull request #3884 from botez/develop

Update iptorrents.py