sky lighting, work in progress
SimpleSkyNode upgrades in progress
SimpleSkyNode: lighting shaders
More work on sky shaders
SkyNode shaders
add lighting effect
update simple sky options
add GL sky
rename lighteffect
Working on getting KML to work better.
Fix silverlining draw order; fix phong lighting setup
simple sky: ramp exposure.
add specular component to the simple sky shader
SimpleSky: fix phong fallback
moved the lighting uniforms helper from mapnode into sky
Remove the old ifdef'ed out code on the KML.
Merge pull request #458 from Thomas-Lerman/lerman-kml

Working on getting KML to work better.
Centralize the lighting shader uniform in Sky.cpp
SkyNode: fixed uniform bugg
Merge branch 'master' of github.com:gwaldron/osgearth