[mythtvnz] playback profiles custom filter

[Brett Miller]

This may only apply to Myth 0.22 (JYA release + fixes 22801) and later.

To get the flesh/skin tones of HD playback to match analogue TV and not look 
rude.
Assumes use of vdpau.
Under frontend playback profiles, edit vdpau profile, change custom filters 
from "vdpaucolor--" to "studio, colorspace=0".

imo This is a great improvement as don't need to adjust TV colour for every 
source.

Brett