Don't let queue_movies fail items because they were already downloaded
Fix check_seed_limits for transmission plugin

The comparison between torrent.seedRatioLimit and torrent.uploadRatio
is inverted when checking against the torrent's own seed ratio limit.
Added try block to make_html to catch RenderErrors
Raise PluginError and log RenderError on make_html
Merge pull request #338 from crawln45/develop

Fix RenderError Crash make_html
Merge pull request #339 from fcharlier/transmission_check_seed_limits

Fix check_seed_limits for transmission plugin