wms_nexrad.earth state features do not draw with image layers enabled

[plevy]

[gwaldron]

<style> block not allowed at the top level, must be inside a <styles> block

[gwaldron]

Also, some of the image layers are drawn with a positive <altitude> which will cause the FeatureModel layer to render behind them. Prob better to use a FeatureImage and draw it before the altitude layers.