Rename fogExp parameter to fogExp2

src/renderers/webgl/WebGLPrograms.js

@@ -31,7 +31,7 @@ function WebGLPrograms( renderer, extensions, capabilities ) {
 		"precision", "supportsVertexTextures", "map", "mapEncoding", "matcap", "matcapEncoding", "envMap", "envMapMode", "envMapEncoding",
 		"lightMap", "aoMap", "emissiveMap", "emissiveMapEncoding", "bumpMap", "normalMap", "objectSpaceNormalMap", "displacementMap", "specularMap",
 		"roughnessMap", "metalnessMap", "gradientMap",
-		"alphaMap", "combine", "vertexColors", "vertexTangents", "fog", "useFog", "fogExp",
+		"alphaMap", "combine", "vertexColors", "vertexTangents", "fog", "useFog", "fogExp2",
 		"flatShading", "sizeAttenuation", "logarithmicDepthBuffer", "skinning",
 		"maxBones", "useVertexTexture", "morphTargets", "morphNormals",
 		"maxMorphTargets", "maxMorphNormals", "premultipliedAlpha",