[MPlayer-dev-eng] support Chinese AVS playback

[Gianluigi Tiesi]

avisynth scripts are not detectables since they are txt files,
just move the detection before the avs demuxer, also
if the file is > 16k it will be skipped by the avisynth
demuxer to avoid crazy memory eating (avisynth tries to load
all the file in memory)

Bye
-- 
Gianluigi Tiesi <sherpya at netfarm.it>
EDP Project Leader
Netfarm S.r.l. - http://www.netfarm.it/
Free Software: http://oss.netfarm.it/