Added renderer config setting PriorityLoading

This can be used to ensure that renderer configs using specific identifying strings take priority over those with overlapping, catch-all strings
Make sure we try to match Panasonic VT60 TV config before the more generic Panasonic TV config
Fixed startup crash on non-Windows operating systems
Fixed bug that caused subtitles to not be transcoded when the renderer supported streaming the file
Fixed renderer priority loading (still very badly implemented!)