Fix Plex track title detection
Fix Plex track title detection

The previous class wasn't sufficiently specific, so it would pull in
extra info and make a match impossible. With this change, the title is
now accurately selected every time.

alexsh/web-scrobbler,Paszt/web-scrobbler,Paszt/web-scrobbler,carpet-berlin/web-scrobbler,galeksandrp/web-scrobbler,usdivad/web-scrobbler,usdivad/web-scrobbler,david-sabata/web-scrobbler,alexsh/web-scrobbler,galeksandrp/web-scrobbler,david-sabata/web-scrobbler,carpet-berlin/web-scrobbler,alexesprit/web-scrobbler,alexesprit/web-scrobbler,fakelbst/Chrome-Last.fm-Scrobbler,inverse/web-scrobbler,ex47/web-scrobbler,ex47/web-scrobbler,fakelbst/Chrome-Last.fm-Scrobbler,inverse/web-scrobbler