150 Compatibility issue: SoVRMLMovieTexture fields alpha, model,
    blendColor and scaleTexCoord missing in Coin.

    This was added for TGS OIV 4.0, so we should implement this for
    compatibility reasons.

    Note that this breaks ABI-compatibility, so it is only relevant
    for Coin 3.

    Note also that these fields break compatibility with the VRML97
    spec if they have non-default values upon export. This should be
    duly noted in their API doc, when written.

    20041010 mortene.
