Fixes SR setting SeedIdleLimit no matter what

Any setting will set a SeedIdleLimit in Transmission even if your client default is to not have SeedIdleLimit enabled. This allows a setting of '-1' to bypass setting the SeedIdleLimit thereby not stopping torrent seeding based on this limit.
Should probably just be remove the reference to sickbeard default '0'. (The default value in the code should be set to -1 too)